usb: musb: force PIO-only if we're building multiplatform kernels

MUSB still needs lots of work on the DMA part
if we want to enable multiple DMA engines on
a multiplatform kernel. Meanwhile, we're forcing
PIO-only so that we, at least, have a working
driver.

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