USB: musb: using 0 instead of NULL

Sparse complains (and rightly so):
drivers/usb/musb/cppi_dma.c:1458:33:
	warning: Using plain integer as NULL pointer

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
1 file changed