scsi: qla2xxx: Fix FC-NVMe LUN discovery

commit a4239945 ("scsi: qla2xxx: Add switch command to simplify
fabric discovery") introduced regression when it did not consider
FC-NVMe code path which broke NVMe LUN discovery.

Fixes: a4239945

 ("scsi: qla2xxx: Add switch command to simplify fabric discovery")
Signed-off-by: Darren Trapp <darren.trapp@cavium.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>