scsi: libfc: fc_rport: Mark expected switch fall-through

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Johannes Thumshirn <jth@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/libfc/fc_rport.c

@@ -1722,6 +1722,7 @@ static void fc_rport_recv_els_req(struct fc_lport *lport, struct fc_frame *fp)
 			kref_put(&rdata->kref, fc_rport_destroy);
 			goto busy;
 		}
+		/* fall through */
 	default:
 		FC_RPORT_DBG(rdata,
 			     "Reject ELS 0x%02x while in state %s\n",