scsi: qla2xxx: Fix WARN_ON in qla_nvme_register_hba

qla_nvme_register_hba() puts out a warning when there are not enough queue
pairs available for FC-NVME.  Just fail the NVME registration rather than a
WARNING + call Trace.

Link: https://lore.kernel.org/r/20200806111014.28434-8-njavali@marvell.com


Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Arun Easi <aeasi@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>