If NO_DMA=y:

drivers/built-in.o: In function `usbhsg_dma_map_ctrl':
mod_gadget.c:(.text+0x53b226): undefined reference to `usb_gadget_map_request'
mod_gadget.c:(.text+0x53b242): undefined reference to `usb_gadget_unmap_request'
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>