Fix to return error code PTR_ERR() from the error handling case instead of
0.

Link: https://lore.kernel.org/r/20200907083949.154251-1-jingxiangfeng@huawei.comAcked-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: Jing Xiangfeng <jingxiangfeng@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>