[Keyboard] Add earth_rover keyboard (#11405)

* Just ./util/new_keyboard.sh earth_rover

* Update readme.md

* Create key layout

* Setup config.h

* Add default keymap

* Fix pins

* Update flash command

* Write info.json

* Add reset instruction

* Change bootloader setting

* Format new C files

* Empty commit for kicking CI

* Update keyboards/earth_rover/config.h

Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>

* Update keyboards/earth_rover/keymaps/default/keymap.c

Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>

* Update readme.md

* Update keyboards/earth_rover/readme.md

Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>

Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>

keyboards/earth_rover/readme.md

@@ -0,0 +1,22 @@
+# earth_rover
+
+![earth_rover](https://pbs.twimg.com/media/Eqh29nYUUAA-9NE?format=jpg)
+
+Mechanical warm, or just cubic macro pad.
+
+* Keyboard Maintainer: [k.bigwheel](https://github.com/bigwheel)
+* Build Guide: [bigwheel/earth\_rover](https://github.com/bigwheel/earth_rover)
+* Hardware Supported: [無限の可能性 \| MxLEDBitPCB](https://swanmatch.github.io/MxLEDBitPCB/), Pro Micro
+* Hardware Availability: [魔界鍵盤製作所 \- BOOTH](https://swanmatch.booth.pm/), [Pro Micro （コンスルー付き） \| 遊舎工房](https://yushakobo.jp/shop/promicro-spring-pinheader/)
+
+Make example for this keyboard (after setting up your build environment):
+
+    make earth_rover:default
+
+Reset Pro Micro by reset button on ProMicroSocket (Red LED must light).
+
+Flashing example for this keyboard:
+
+    make earth_rover:default:flash
+
+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).