[media] v4l: vsp1: dl: Make reg_count field unsigned

The field takes positive values only, make it unsigned.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/platform/vsp1/vsp1_dl.c

@@ -60,7 +60,7 @@ struct vsp1_dl_list {
 	dma_addr_t dma;
 	size_t size;
 
-	int reg_count;
+	unsigned int reg_count;
 };
 
 enum vsp1_dl_mode {