Usb: gadget: [HACK] get FunctionFS and Android USB to build together

The configs cannot both be activated at the same time, but Android USB now needs FunctionFS for ADB, MTP, and other functions, so we'll put them under the same config, so they go together like lamb and tuna fish

Change-Id: I85bf6be04289dc3dea17e226330d377aa25d8125
defconfig: switch to GPIO_MSM_v3 in defconfig so that Kconfig doesn't conflict

Change-Id: I6cfb4528fc911b6d17c1a32657516f374f2426bf