Tidy 40percentclub boards (#4403)

* Remove unnecessary re-definitions for XXXXXXX and _______

* Update 6lit to use KC_NO in layout macros

* Update rules.mk to follow current template

* Remove use of deprecated function action_get_macro - unused and contents were from old template

* Remove use of deprecated function action_get_macro - all code was commented out

* Remove use of deprecated function action_get_macro - convert macro to use process_record_user

* Convert keymap to consistent use of _______

* fix use of old style header guards

* Swap KC_NO for XXXXXXX macro since the swap to the macro for KC_TRANS

* Resolve use of ?= in rules.mk files

* Remove duplication of rules.mk and config.h in gherkin mjt keymap

* Remove unnecessary #includes

* Align layout macros so foobar can use gherkin keymaps

* Align 6lit layout macros with foobar

* Remove ifndef QUANTUM_DIR from keymaps

keyboards/40percentclub/nano/keymaps/default/keymap.c

@@ -3,7 +3,6 @@
 #define _MAIN 0
 #define _FN 1
 
-#define _______ KC_TRNS
 #define KC_X0 LT(_FN, KC_ESC)
 
 const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {

keyboards/40percentclub/nano/keymaps/spooka/keymap.c

@@ -2,8 +2,6 @@
 
 #define _MAIN 0
 
-#define _______ KC_TRNS
-
 const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
   [_MAIN] = LAYOUT(
      RGB_TOG, RGB_HUI, RGB_SAI, RGB_VAI,