Discourage use of ENCODER_MAP at keyboard level (#18286)

* Discourage use of ENCODER_MAP at keyboard level

* Update docs/feature_encoders.md

Co-authored-by: Ryan <fauxpark@gmail.com>

Co-authored-by: Ryan <fauxpark@gmail.com>

docs/feature_encoders.md

@@ -69,7 +69,7 @@ Additionally, if one side does not have an encoder, you can specify `{}` for the
 
 ## Encoder map :id=encoder-map
 
-Encoder mapping may be added to your `keymap.c`, which replicates the normal keyswitch layer handling functionality, but with encoders. Add this to your `rules.mk`:
+Encoder mapping may be added to your `keymap.c`, which replicates the normal keyswitch layer handling functionality, but with encoders. Add this to your keymap's `rules.mk`:
 
 ```make
 ENCODER_MAP_ENABLE = yes
@@ -88,6 +88,8 @@ const uint16_t PROGMEM encoder_map[][NUM_ENCODERS][2] = {
 #endif
 ```
 
+?> This should only be enabled at the keymap level.
+
 ## Callbacks
 
 When not using `ENCODER_MAP_ENABLE = yes`, the callback functions can be inserted into your `<keyboard>.c`:

docs/pr_checklist.md

@@ -67,6 +67,9 @@ https://github.com/qmk/qmk_firmware/pulls?q=is%3Apr+is%3Aclosed+label%3Akeyboard
     - no `(-/+size)` comments related to enabling features
     - remove the list of alternate bootloaders if one has been specified
     - no re-definitions of the default MCU parameters if same value, when compared to the equivalent MCU in [mcu_selection.mk](https://github.com/qmk/qmk_firmware/blob/master/builddefs/mcu_selection.mk)
+    - no "keymap only" features enabled
+      - `COMBO_ENABLE`
+      - `ENCODER_MAP_ENABLE`
 - keyboard `config.h`
     - don't repeat `MANUFACTURER` in the `PRODUCT` value
     - no `#define DESCRIPTION`