[Keyboard] Add pi40 (#18207)

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

keyboards/1upkeyboards/pi40/readme.md

@@ -0,0 +1,38 @@
+# pi40
+
+![pi40](https://i.imgur.com/ONVtaVZh.jpeg)
+
+The pi40 is a 4x12 ortholinear keyboard with a fixed 2u spacebar using a Raspberry Pi Pico for the controller.
+
+It includes options for a rotary encoder, SSD1306 oled, and per-key in-switch RGB LEDs.
+
+All unused GPIO pins are broken out on the main pcb, as well as the available voltage pins.
+
+This firmware also includes the option for VIA which includes configuration options for the rotary encoder, matrix lighting, and up to 10 layers.
+
+Default oled configuration displays:
+   - current layer
+   - caps lock status
+   - num lock status
+   - scroll lock status
+   - current RGB lighting mode
+
+* Keyboard Maintainer: [ziptyze](https://github.com/ziptyze)
+* Hardware Availability: (https://1upkeyboards.com/shop/keyboard-kits/diy-40-kits/pi40-keyboard-kit/)
+
+Make example for this keyboard (after setting up your build environment):
+
+    make 1upkeyboards/pi40:default
+
+Flashing example for this keyboard:
+
+    make 1upkeyboards/pi40: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).
+
+## Bootloader
+
+Enter the bootloader in 2 ways:
+
+* **Bootmagic reset**: Hold down the key at (0,0) in the matrix, the top left key, and plug in the keyboard
+* **BOOTSEL button**: Hold down the BOOTSEL button on the pico, and plug in the keyboard