scsi: pm8001: Remove unnecessary OOM message

Fixes scripts/checkpatch.pl warning:
WARNING: Possible unnecessary 'out of memory' message

Remove it can help us save a bit of memory.

Also change the return error code from "-1" to "-ENOMEM".

Link: https://lore.kernel.org/r/20210610094605.16672-2-thunder.leizhen@huawei.com
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>