[Keyboard] handwired/m40/5x5_macropad (#16288)

* Adding the custom handwired 5x5 macropad.

* Update keyboards/handwired/m40/5x5_macropad/readme.md

* Update keyboards/handwired/m40/5x5_macropad/rules.mk

* Update keyboards/handwired/m40/5x5_macropad/readme.md

* Update readme.md

fixed the github link to my profile

* Update keyboards/handwired/m40/5x5_macropad/5x5_macropad.c

* Update keyboards/handwired/m40/5x5_macropad/5x5_macropad.h

* Update keyboards/handwired/m40/5x5_macropad/5x5_macropad.h

* Update keyboards/handwired/m40/5x5_macropad/config.h

* Update keyboards/handwired/m40/5x5_macropad/readme.md

* Update keyboards/handwired/m40/5x5_macropad/config.h

* Update keyboards/handwired/m40/5x5_macropad/readme.md

* Update keyboards/handwired/m40/5x5_macropad/keymaps/default/keymap.c

* Apply suggestions from code review

* added discord Id for maintainer contact

* Update keyboards/handwired/m40/5x5_macropad/readme.md

* Update keyboards/handwired/m40/5x5_macropad/info.json

keyboards/handwired/m40/5x5_macropad/rules.mk

@@ -0,0 +1,22 @@
+# MCU name
+MCU = atmega32u4
+
+# Bootloader selection
+BOOTLOADER = caterina
+
+# Build Options
+#   change yes to no to disable
+#
+BOOTMAGIC_ENABLE = no       # Enable Bootmagic Lite
+MOUSEKEY_ENABLE = yes       # Mouse keys
+EXTRAKEY_ENABLE = yes       # Audio control and System control
+CONSOLE_ENABLE = no         # Console for debug
+COMMAND_ENABLE = yes        # Commands for debug and configuration
+NKRO_ENABLE = no            # Enable N-Key Rollover
+BACKLIGHT_ENABLE = no       # Enable keyboard backlight functionality
+RGBLIGHT_ENABLE = no        # Enable keyboard RGB underglow
+AUDIO_ENABLE = no           # Audio output
+
+# Disable unsupported hardware
+AUDIO_SUPPORTED = no
+BACKLIGHT_SUPPORTED = no