linux-imx

dmaengine: xgene: devm_ioremap() returns NULL on error

The code here is checking for IS_ERR() but devm_ioremap() returns NULL
on error and not an error pointer.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>