Make default layer size 16-bit (#15286)

Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>

keyboards/splitkb/kyria/keymaps/j-inc/keymap.c

@@ -341,7 +341,7 @@ bool oled_task_user(void) {
 
 #ifdef ENCODER_ENABLE
 bool encoder_update_user(uint8_t index, bool clockwise) {
-    switch(biton32(layer_state)){
+    switch(get_highest_layer(layer_state)){
         case 1:
             if (clockwise) {
                 tap_code16(C(KC_TAB));