Turn off touchio on pIRkey and add back usb midi.

USB MIDI was still being compiled in mostly anyway. There is no
place to touch on the board so touchio is useless.

Author: tannewt

ports/atmel-samd/boards/pirkey_m0/mpconfigboard.mk

@@ -16,7 +16,8 @@ CIRCUITPY_NEOPIXEL_WRITE = 0
 CIRCUITPY_ROTARYIO = 0
 CIRCUITPY_RTC = 0
 CIRCUITPY_SAMD = 0
-CIRCUITPY_USB_MIDI = 0
+CIRCUITPY_USB_MIDI = 1
+CIRCUITPY_TOUCHIO = 0
 CIRCUITPY_SMALL_BUILD = 1
 
 CHIP_VARIANT = SAMD21E18A