[Keyboard] Helix use `post_rules.mk` (#14216)

* Helix/pico use post_rules.mk insted of local_features.mk

Tested with the following procedure.
```
git checkout 77a93fec79 (qmk/develop)
make clean
make helix/pico:all:check-md5
make helix/pico/sc:all:check-md5
git checkout helix_use_post_rules.mk
make clean
make helix/pico:all:check-md5
make helix/pico/sc:all:check-md5
```

* Helix/rev2 use post_rules.mk

Tested with the following procedure.
```
git checkout 77a93fec79 (qmk/develop)
make clean
make helix/pico:all:check-md5
make helix/pico/sc:all:check-md5
make helix/rev2:all:check-md5
make helix/rev2/sc:all:check-md5
git checkout helix_use_post_rules.mk
make clean
make helix/pico:all:check-md5
make helix/pico/sc:all:check-md5
make helix/rev2:all:check-md5
make helix/rev2/sc:all:check-md5
```

9 files changed, 3 insertions, 32 deletions

diff --git a/keyboards/helix/rev2/keymaps/default/rules.mk b/keyboards/helix/rev2/keymaps/default/rules.mk
index c16f3e2b87..58b43a6bda 100644
--- a/keyboards/helix/rev2/keymaps/default/rules.mk
+++ b/keyboards/helix/rev2/keymaps/default/rules.mk
@@ -29,7 +29,3 @@ OLED_SELECT = core
 ifeq ($(strip $(OLED_ENABLE)), yes)
     SRC += oled_display.c
 endif
-
-# convert Helix-specific options (that represent combinations of standard options)
-#   into QMK standard options.
-include $(strip $(KEYBOARD_LOCAL_FEATURES_MK))
diff --git a/keyboards/helix/rev2/keymaps/five_rows/rules.mk b/keyboards/helix/rev2/keymaps/five_rows/rules.mk
index e59ce73326..5f7e4668fc 100644
--- a/keyboards/helix/rev2/keymaps/five_rows/rules.mk
+++ b/keyboards/helix/rev2/keymaps/five_rows/rules.mk
@@ -95,7 +95,3 @@ endif
 ifeq ($(strip $(OLED_ENABLE)), yes)
     SRC += oled_display.c
 endif
-
-# convert Helix-specific options (that represent combinations of standard options)
-#   into QMK standard options.
-include $(strip $(KEYBOARD_LOCAL_FEATURES_MK))
diff --git a/keyboards/helix/rev2/keymaps/five_rows_jis/rules.mk b/keyboards/helix/rev2/keymaps/five_rows_jis/rules.mk
index d44382f86a..7c4a7b6045 100644
--- a/keyboards/helix/rev2/keymaps/five_rows_jis/rules.mk
+++ b/keyboards/helix/rev2/keymaps/five_rows_jis/rules.mk
@@ -17,7 +17,3 @@ HELIX_ROWS = 5              # Helix Rows is 4 or 5
 # LED_UNDERGLOW_ENABLE = no   # LED underglow (Enable WS2812 RGB underlight.)
 # LED_ANIMATIONS = yes        # LED animations
 # IOS_DEVICE_ENABLE = no      # connect to IOS device (iPad,iPhone)
-
-# convert Helix-specific options (that represent combinations of standard options)
-#   into QMK standard options.
-include $(strip $(KEYBOARD_LOCAL_FEATURES_MK))
diff --git a/keyboards/helix/rev2/keymaps/fraanrosi/rules.mk b/keyboards/helix/rev2/keymaps/fraanrosi/rules.mk
index 462a83f6e7..98585b0d60 100644
--- a/keyboards/helix/rev2/keymaps/fraanrosi/rules.mk
+++ b/keyboards/helix/rev2/keymaps/fraanrosi/rules.mk
@@ -22,7 +22,3 @@ LED_ANIMATIONS = yes        # LED animations
 
 LED_BACK_ENABLE = no
 LED_UNDERGLOW_ENABLE = yes
-
-# convert Helix-specific options (that represent combinations of standard options)
-#   into QMK standard options.
-include $(strip $(KEYBOARD_LOCAL_FEATURES_MK))
diff --git a/keyboards/helix/rev2/keymaps/froggy/rules.mk b/keyboards/helix/rev2/keymaps/froggy/rules.mk
index 5a0fd9a2b1..2d01c43fe7 100644
--- a/keyboards/helix/rev2/keymaps/froggy/rules.mk
+++ b/keyboards/helix/rev2/keymaps/froggy/rules.mk
@@ -17,7 +17,3 @@ LED_BACK_ENABLE = yes       # LED backlight (Enable WS2812 RGB underlight.)
 LED_UNDERGLOW_ENABLE = no   # LED underglow (Enable WS2812 RGB underlight.)
 LED_ANIMATIONS = yes        # LED animations
 # IOS_DEVICE_ENABLE = no      # connect to IOS device (iPad,iPhone)
-
-# convert Helix-specific options (that represent combinations of standard options)
-#   into QMK standard options.
-include $(strip $(KEYBOARD_LOCAL_FEATURES_MK))
diff --git a/keyboards/helix/rev2/keymaps/froggy_106/rules.mk b/keyboards/helix/rev2/keymaps/froggy_106/rules.mk
index 5a0fd9a2b1..2d01c43fe7 100644
--- a/keyboards/helix/rev2/keymaps/froggy_106/rules.mk
+++ b/keyboards/helix/rev2/keymaps/froggy_106/rules.mk
@@ -17,7 +17,3 @@ LED_BACK_ENABLE = yes       # LED backlight (Enable WS2812 RGB underlight.)
 LED_UNDERGLOW_ENABLE = no   # LED underglow (Enable WS2812 RGB underlight.)
 LED_ANIMATIONS = yes        # LED animations
 # IOS_DEVICE_ENABLE = no      # connect to IOS device (iPad,iPhone)
-
-# convert Helix-specific options (that represent combinations of standard options)
-#   into QMK standard options.
-include $(strip $(KEYBOARD_LOCAL_FEATURES_MK))
diff --git a/keyboards/helix/rev2/keymaps/led_test/rules.mk b/keyboards/helix/rev2/keymaps/led_test/rules.mk
index 8b590eee86..3ab27acfc2 100644
--- a/keyboards/helix/rev2/keymaps/led_test/rules.mk
+++ b/keyboards/helix/rev2/keymaps/led_test/rules.mk
@@ -23,7 +23,3 @@ ifeq ($(strip $(OLED_ENABLE)), yes)
     SRC += oled_display.c
 endif
 SRC += led_test_init.c
-
-# convert Helix-specific options (that represent combinations of standard options)
-#   into QMK standard options.
-include $(strip $(KEYBOARD_LOCAL_FEATURES_MK))
diff --git a/keyboards/helix/rev2/keymaps/yshrsmz/rules.mk b/keyboards/helix/rev2/keymaps/yshrsmz/rules.mk
index 83dcc9b3b8..cd436cd9a3 100644
--- a/keyboards/helix/rev2/keymaps/yshrsmz/rules.mk
+++ b/keyboards/helix/rev2/keymaps/yshrsmz/rules.mk
@@ -17,7 +17,3 @@ OLED_ENABLE = yes            # OLED_ENABLE
 # LED_UNDERGLOW_ENABLE = no   # LED underglow (Enable WS2812 RGB underlight.)
 LED_ANIMATIONS = no        # LED animations
 # IOS_DEVICE_ENABLE = no      # connect to IOS device (iPad,iPhone)
-
-# convert Helix-specific options (that represent combinations of standard options)
-#   into QMK standard options.
-include $(strip $(KEYBOARD_LOCAL_FEATURES_MK))
diff --git a/keyboards/helix/rev2/post_rules.mk b/keyboards/helix/rev2/post_rules.mk
new file mode 100644
index 0000000000..4c671d4515
--- /dev/null
+++ b/keyboards/helix/rev2/post_rules.mk
@@ -0,0 +1,3 @@
+ifneq ($(strip $(KEYBOARD_LOCAL_FEATURES_MK)),)
+  include $(strip $(KEYBOARD_LOCAL_FEATURES_MK))
+endif