Add the missing unlock on the error handling path in function
imxdma_xfer_desc().
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NVinod Koul <vinod.koul@linux.intel.com>