usb: gadget: uvc: use explicit type instead of void *

The first parameter of __uvcg_iter_strm_cls() is always used in
the context of struct uvcg_streaming_header, so change the
function prototype accordingly.
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/function/uvc_configfs.c

@@ -1918,10 +1918,10 @@ enum uvcg_strm_type {
 	UVCG_FRAME
 };
 
-static int __uvcg_iter_strm_cls(void *priv1, void *priv2, void *priv3,
+static int __uvcg_iter_strm_cls(struct uvcg_streaming_header *h,
+	void *priv2, void *priv3,
 	int (*fun)(void *, void *, void *, int, enum uvcg_strm_type type))
 {
-	struct uvcg_streaming_header *h = priv1;
 	struct uvcg_format_ptr *f;
 	struct config_group *grp;
 	struct config_item *item;