Clean-up of `#define _ADJUST 16` instances (#18182)

* enum layer_names: 40percentclub/nori default keymap

* enum layer_names: ergotravel default keymap

* enum layer_names: handwired/atreus50 default keymap

* enum layer_names: handwired/ortho5x13 default keymap

* enum layer_names: keebio/levinson default keymap

* enum layer_names: keebio/nyquist default keymap

* enum layer_names: keebio/rorschach default keymap

* enum layer_names: keebio/viterbi default keymap

* enum layer_names: keebio/wavelet default keymap

* enum layer_names: lets_split default keymap

* enum layer_names: maple_computing/launchpad reference keymaps

Update `default` and `default_rgb` keymaps.

* enum layer_names: maple_computing/minidox default keymap

* enum layer_names: miniaxe reference keymaps

Update `default` and `underglow` keymaps.

* enum layer_names: omkbd/ergodash/mini default keymap

* enum layer_names: omkbd/ergodash/rev1 default keymap

* enum layer_names: orthodox default keymap

* enum layer_names: unikeyboard/divergetm2 default keymap

* enum layer_names: woodkeys/scarletbandana default keymap

* add _Static_assert to keymap_introspection.c

1 files changed, 8 insertions, 6 deletions

diff --git a/keyboards/lets_split/keymaps/default/keymap.c b/keyboards/lets_split/keymaps/default/keymap.c
index bc240b5f00..34b470d533 100644
--- a/keyboards/lets_split/keymaps/default/keymap.c
+++ b/keyboards/lets_split/keymaps/default/keymap.c
@@ -4,12 +4,14 @@
 // The underscores don't mean anything - you can have a layer called STUFF or any other name.
 // Layer names don't all need to be of the same length, obviously, and you can also skip them
 // entirely and just use numbers.
-#define _QWERTY 0
-#define _COLEMAK 1
-#define _DVORAK 2
-#define _LOWER 3
-#define _RAISE 4
-#define _ADJUST 16
+enum layer_names {
+    _QWERTY,
+    _COLEMAK,
+    _DVORAK,
+    _LOWER,
+    _RAISE,
+    _ADJUST
+};
 
 enum custom_keycodes {
   QWERTY = SAFE_RANGE,