[SCSI] libfc: fix stats computation in fc_queuecommand()

There seems accumulation needed.
Signed-off-by: NHillf Danton <dhillf@gmail.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

drivers/scsi/libfc/fc_fcp.c

@@ -1820,11 +1820,11 @@ static int fc_queuecommand_lck(struct scsi_cmnd *sc_cmd, void (*done)(struct scs
 	if (sc_cmd->sc_data_direction == DMA_FROM_DEVICE) {
 		fsp->req_flags = FC_SRB_READ;
 		stats->InputRequests++;
-		stats->InputMegabytes = fsp->data_len;
+		stats->InputMegabytes += fsp->data_len;
 	} else if (sc_cmd->sc_data_direction == DMA_TO_DEVICE) {
 		fsp->req_flags = FC_SRB_WRITE;
 		stats->OutputRequests++;
-		stats->OutputMegabytes = fsp->data_len;
+		stats->OutputMegabytes += fsp->data_len;
 	} else {
 		fsp->req_flags = 0;
 		stats->ControlRequests++;