[keyboard] Plain60 cleanups (#7644)

* Change plain60 to bootmagic lite

 - it's easier to reset and maintain a keyboard with lite
 - remove obsolete size comments

* Add RESET on a layer to default keymap

* Use _FN

* Maintain compatibility with keymap

* Fix thinko

keyboards/maartenwut/plain60/keymaps/default/keymap.c

@@ -4,7 +4,10 @@
 // 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 _MA 0
+enum _layer {
+  _MA,
+  _FN
+};
 
 const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
 
@@ -12,6 +15,13 @@ const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
   KC_ESC,  KC_1,    KC_2,   KC_3,   KC_4,   KC_5,   KC_6,   KC_7,   KC_8,   KC_9,    KC_0,    KC_MINS, KC_EQL,  KC_BSLS, KC_BSPC, \
   KC_TAB,  KC_Q,    KC_W,   KC_E,   KC_R,   KC_T,   KC_Y,   KC_U,   KC_I,   KC_O,    KC_P,    KC_LBRC, KC_RBRC, KC_BSLS,          \
   KC_CAPS, KC_A,    KC_S,   KC_D,   KC_F,   KC_G,   KC_H,   KC_J,   KC_K,   KC_L,    KC_SCLN, KC_QUOT, KC_BSLS, KC_ENT,           \
-  KC_LSFT, KC_NUBS, KC_Z,   KC_X,   KC_C,   KC_V,   KC_B,   KC_N,   KC_M,   KC_COMM, KC_DOT,  KC_SLSH, KC_RSFT, KC_UP,            \
-  KC_LCTL, KC_LGUI, KC_LALT,                        KC_SPC,                          KC_RALT, KC_RGUI, KC_APP,  KC_RCTRL)
+  KC_LSFT, KC_NUBS, KC_Z,   KC_X,   KC_C,   KC_V,   KC_B,   KC_N,   KC_M,   KC_COMM, KC_DOT,  KC_SLSH, KC_RSFT, LT(_FN, KC_UP),   \
+  KC_LCTL, KC_LGUI, KC_LALT,                        KC_SPC,                          KC_RALT, KC_RGUI, LT(_FN, KC_APP),  KC_RCTRL),
+
+[_FN] = LAYOUT(
+  _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, \
+  _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, RESET,   \
+  _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,  \
+  _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,  \
+  _______, _______, _______,                            _______,                            _______, _______, _______, _______)
 };

keyboards/maartenwut/plain60/rules.mk

@@ -14,14 +14,14 @@ BOOTLOADER = qmk-dfu
 # Build Options
 #   comment out to disable the options.
 #
-BOOTMAGIC_ENABLE = no	# Virtual DIP switch configuration(+1000)
-MOUSEKEY_ENABLE = no	# Mouse keys(+4700)
-EXTRAKEY_ENABLE = yes	# Audio control and System control(+450)
-CONSOLE_ENABLE = no	# Console for debug(+400)
+BOOTMAGIC_ENABLE = lite	# Virtual DIP switch configuration
+MOUSEKEY_ENABLE = no	# Mouse keys
+EXTRAKEY_ENABLE = yes	# Audio control and System control
+CONSOLE_ENABLE = no	# Console for debug
 COMMAND_ENABLE = no    # Commands for debug and configuration
 NKRO_ENABLE = no		# USB Nkey Rollover - if this doesn't work, see here: https://github.com/tmk/tmk_keyboard/wiki/FAQ#nkro-doesnt-work
-RGBLIGHT_ENABLE = no   # Enable keyboard underlight functionality (+4870)
-BACKLIGHT_ENABLE = no  # Enable keyboard backlight functionality (+1150)
+RGBLIGHT_ENABLE = no   # Enable keyboard underlight functionality
+BACKLIGHT_ENABLE = no  # Enable keyboard backlight functionality
 MIDI_ENABLE = no 		# MIDI controls
 AUDIO_ENABLE = no
 UNICODE_ENABLE = no 		# Unicode