drbd: Remove unneeded semicolon

Fixes coccicheck warning:

drivers/block/drbd/drbd_req.c:887:2-3: Unneeded semicolon
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/block/drbd/drbd_req.c

@@ -884,7 +884,7 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		start_new_tl_epoch(connection);
 		mod_rq_state(req, m, 0, RQ_NET_OK|RQ_NET_DONE);
 		break;
-	};
+	}
 
 	return rv;
 }