usb: musb: fix DMA for host mode

Commit ac33cdb1 ("usb: musb: Remove ifdefs for musb_host_rx in
musb_host.c part5") introduces a problem setting DMA host mode.

The musb_advance_schedule() is called immediately after receiving an
endpoint RX interrupt without waiting for the DMA transfer to complete.

As a consequence when the dma complete interrupt arrives the in_qh
member of hw_ep is already null an the musb_host_rx() exits on !urb
error case. Fix the done condition that advances the musb schedule.

Signed-off-by: Cristian Birsan <cristian.birsan@microchip.com>
Signed-off-by: Joshua Henderson <joshua.henderson@microchip.com>
Tested-by: Ladislav Michl <ladis@linux-mips.org>
Signed-off-by: Felipe Balbi <balbi@kernel.org>