scsi: ibmvscsis: Fix a stringop-overflow warning

There's currently a warning about string overflow with strncat:

drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c: In function 'ibmvscsis_probe':
drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c:3479:2: error: 'strncat' specified
bound 64 equals destination size [-Werror=stringop-overflow=]
  strncat(vscsi->eye, vdev->name, MAX_EYE);
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Switch to a single snprintf instead of a strcpy + strcat to handle this
cleanly.
Signed-off-by: Laura Abbott <labbott@redhat.com>
Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c

@@ -3474,8 +3474,7 @@ static int ibmvscsis_probe(struct vio_dev *vdev,
 		vscsi->dds.window[LOCAL].liobn,
 		vscsi->dds.window[REMOTE].liobn);
 
-	strcpy(vscsi->eye, "VSCSI ");
-	strncat(vscsi->eye, vdev->name, MAX_EYE);
+	snprintf(vscsi->eye, sizeof(vscsi->eye), "VSCSI %s", vdev->name);
 
 	vscsi->dds.unit_id = vdev->unit_address;
 	strncpy(vscsi->dds.partition_name, partition_name,