WIP: Sofle config with APM32 support.

[timbrown5]

A bad attempt to reverse engineer a config for an AliExpress Sofle.

Current situation:
I have checked which pins are connected to what with a multimeter, and here's what I found:

• left cols PA3, PA4, PA5, PB0, PB1, PB2
• left rows PB11, PB10, PA7, PA6 PB9
• right cols: PB9, PC13, PC14, PC15, PA7, PA6
• right rows: PA13, PB3, PB4. PB5, PB8
• serial pin: PA2
• LED in B15
• Encoder: pin-a: PA1, pin-b PA0
• the new config I've written - the firmware compiles and flashes.
• the RGB doesn't light up (I tried copying the config from cannonkeys/tsukuyomi, but I think I've done something wrong).
• the keys don't work - I remapped them based on the pin IDs from the Geehy datasheet and the values above.
• I got some debug info from HID console.

oled_init cmd set 1 failed
Keyboard booting up...

Notes:
I found the cannonkeys/tsukuyomi firmware flashed and lit up the LEDs (obviously the keymap is wrong), so I used that as a basis for the RBG config. I think I should be using rgb_matrix
I'm trying to get rgblight working for now as it's similar to the other 'working' config which at least lights the LEDs.