[Keyboard] Add TMKL PCB (#11173)

* add

* update

* update indicator LED

* Update keyboards/mechlovin/tmkl/keymaps/default/keymap.c

Co-authored-by: Joel Challis <git@zvecr.com>

* Update keyboards/mechlovin/tmkl/readme.md

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

Co-authored-by: vuhopkep <boy9x0@gmail.com>
Co-authored-by: Joel Challis <git@zvecr.com>
Co-authored-by: Ryan <fauxpark@gmail.com>

keyboards/mechlovin/tmkl/rules.mk

@@ -0,0 +1,17 @@
+# MCU name
+MCU = STM32F303
+
+# Build Options
+#   change yes to no to disable
+#
+BOOTMAGIC_ENABLE = lite     # Virtual DIP switch configuration
+MOUSEKEY_ENABLE = yes       # Mouse keys
+EXTRAKEY_ENABLE = yes       # Audio control and System control
+CONSOLE_ENABLE = yes        # Console for debug
+COMMAND_ENABLE = yes        # Commands for debug and configuration
+# Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
+SLEEP_LED_ENABLE = no       # Breathing sleep LED during USB suspend
+# if this doesn't work, see here: https://github.com/tmk/tmk_keyboard/wiki/FAQ#nkro-doesnt-work
+NKRO_ENABLE = yes           # USB Nkey Rollover
+BACKLIGHT_ENABLE = yes      # Enable keyboard backlight functionality
+RGBLIGHT_ENABLE = no        # Enable keyboard RGB underglow