[Keyboard] XD75 refactor (#5420)

* Refactor layout macro names

Update the names of the layout macros to reflect QMK's desired usage.

- KEYMAP renamed to LAYOUT
  - colinta keymap updated accordingly
- KC_KEYMAP renamed to LAYOUT_kc
  - mtdjr keymap updated accordingly

* Update xd75.h to use #pragma once include guard

* Update keymaps to use QMK_KEYBOARD_H

* Refactor default keymap

- updated to use layout macro
- remove deprecated action_get_macro function
- add functions from QMK keymap.c template
  - process_record_user
  - matrix_init_user
  - matrix_scan_user
  - led_set_user

* Update supporting files

- updated config.h files to use #pragma once include guard
- remove errant QUANTUM_DIR code block

* Rename readme files to fully lowercase filenames

* Restructure keyboard readme

Updated the readme to better align with the current QMK template.

* Bugfixes to supporting files

1 files changed, 12 insertions, 39 deletions

diff --git a/keyboards/xd75/readme.md b/keyboards/xd75/readme.md
index e11ce7dca..fc5b8972c 100644
--- a/keyboards/xd75/readme.md
+++ b/keyboards/xd75/readme.md
@@ -1,32 +1,25 @@
-xd75 keyboard firmware
-======================
+# XD75
 
-The XD75Re is a 15x5 full-grid ortholinear keyboard manufactured by XIUDI. This port of the QMK firmware is my first shot at using QMK, so if you see any features done wrong (or just plain missing), feel free to fix them and put in a pull request!
+![XD75](https://cdn.shopify.com/s/files/1/2711/4238/products/HTB1MzOISXXXXXXgXpXXq6xXFXXXO_1024x1024.jpg)
 
-## Quantum MK Firmware
+The XD75Re is a 15x5 full-grid ortholinear keyboard manufactured by XIUDI. This port of the QMK firmware is my first shot at using QMK, so if you see any features done wrong (or just plain missing), feel free to fix them and put in a pull request!
 
-For more info on this firmware (and how to make it your own), head over to [qmk.fm](http://qmk.fm).
+Keyboard Maintainer: [The QMK Community](https://github.com/qmk)  
+Hardware Supported: XD75Re  
+Hardware Availability: [KPrepublic](https://kprepublic.com/products/xd75re-xd75am-xd75-xiudi-60-custom-keyboard-pcb), [AliExpress](https://www.aliexpress.com/item/xd75re-Custom-Mechanical-Keyboard-75-keys-TKG-TOOLS-Underglow-RGB-PCB-GH60-60-programmed-gh60-kle/32818745981.html)
 
-## Building
+Make example for this keyboard (after setting up your build environment):
 
-Download or clone the whole firmware and navigate to the
-keyboards/xd75 folder. Once your dev env is setup, you'll be able to
-type `make` to generate your .hex - you can then use the Teensy Loader
-to install the resulting .hex file, or have the `make` process install
-it using DFU.
+    make xd75:default
 
-### Default
+Flashing example:
 
-To build with the default keymap, simply run `make xd75:default` from the root directory (i.e. two levels above this file), and to install via DFU, `make xd75:default:dfu`, also from the root directory.
+    make xd75:default:dfu
 
-Note that DFU is likely to require root permissions, so installing the
-firmware likely requires a command line like:
+See the [build environment setup](https://docs.qmk.fm/#/getting_started_build_tools) and the [make instructions](https://docs.qmk.fm/#/getting_started_make_guide) for more information. Brand new to QMK? Start with our [Complete Newbs Guide](https://docs.qmk.fm/#/newbs).
 
-```
-$ sudo make xd75:default:dfu
-```
 
-### LED control
+## LED control
 
 There are 3 individual LEDs that can be turned on and off, plus the keycap LEDs (which are all wired into the same pin).  The functions are named according to how they're labeled on the PCB.
 
@@ -65,23 +58,3 @@ GP103_LED       F4
 KEYCAPS_LED     F5
 GP100_LED       F7
 ```
-
-### Other Keymaps
-
-The "default" keymap included is basically the OLKB Atomic keymap with
-a few buttons added for RGB underglow control. This should be usable
-as a starting point, but most people will be best served creating
-their own keymap and flashing it - more info on creating your own
-keymap is available in [the official QMK
-documentation](https://docs.qmk.fm).
-
-Keymaps follow the format **__\<name\>.c__** and are stored in
-subdirectories under `keyboards/xd75/keymaps`
-
-To build the firmware binary hex file for a specific keymap, and
-install it, using DFU, just do `make` with a keymap like this:
-
-```
-$ make xd75:[default|<name>]
-```
-