Add 1209/9210 Mimic X (kunichiko)

[kunichiko]

Requesting PID 0x1209:0x9210 for Mimic X.

• Device: USB-MIDI receiver that emulates retro-PC HID peripherals (ATARI joystick, Sega Mega Drive 6-button pad, Sharp X68000 keyboard and mouse) for retro computers, driven from a smartphone over USB-MIDI. Built around the WCH CH32X035 MCU.
• Firmware repo (MIT): https://github.com/kunichiko/MimicX-firmware
• Hardware repo (MIT): https://github.com/kunichiko/MimicX-hardware
• Both repos have LICENSE files (MIT) and contain modifiable sources (firmware code and KiCad-style PCB design).
• This is the organisation's first PID and registers a new kunichiko org page.