scsi: libfc: pass an error pointer to fc_disc_error()

This patch is basically to silence a static checker warning.

    drivers/scsi/libfc/fc_disc.c:326 fc_disc_error()
    warn: passing a valid pointer to 'PTR_ERR'

It doesn't affect runtime because it treats -ENOMEM and a valid pointer
the same.  But the documentation says we should be passing an error
pointer.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Johannes Thumshirn <jth@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/libfc/fc_disc.c

@@ -573,7 +573,7 @@ static void fc_disc_gpn_ft_resp(struct fc_seq *sp, struct fc_frame *fp,
 		event = DISC_EV_FAILED;
 	}
 	if (error)
-		fc_disc_error(disc, fp);
+		fc_disc_error(disc, ERR_PTR(error));
 	else if (event != DISC_EV_NONE)
 		fc_disc_done(disc, event);
 	fc_frame_free(fp);