usb: musb: ux500: add dma glue layer for ux500

Unaligned sizes and buffers are not supported and they will be filtered
out by is_compatible().

Signed-off-by: Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>