Update mpconfigboard.mk

Add build flags to turn off subsystems which are not relevant to the USB Hub

Author: osterwood

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

@@ -12,3 +12,16 @@ LONGINT_IMPL = MPZ
 
 # No I2S on SAMD51G
 CIRCUITPY_AUDIOBUSIO = 0
+
+CIRCUITPY_FULL_BUILD = 0
+CIRCUITPY_AUDIOIO = 0
+CIRCUITPY_AUDIOCORE = 0
+CIRCUITPY_COUNTIO = 0
+CIRCUITPY_ROTARYIO = 0
+CIRCUITPY_TOUCHIO = 0
+CIRCUITPY_SDCARDIO = 0
+CIRCUITPY_NEOPIXEL_WRITE = 0
+CIRCUITPY_PIXELBUF = 0
+CIRCUITPY_GAMEPAD = 0
+CIRCUITPY_USB_HID = 0
+CIRCUITPY_USB_MIDI = 0