usb: gadget: mv_udc: fix dtd dma confusion

The controller will prime failure sometimes when do the iperf test.
Add delay to wait controller release dtd dma before we free it.
Then the issue is gone.

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