V4L/DVB: v4l2-subdev.h: fix enum_mbus_fmt prototype

enum_mbus_fmt received an index argument that was defined as an int instead
of an unsigned int. This is now fixed. This had the knock-on effect that the
index argument in the callback get_formats in soc_camera.h also had to be
changed to unsigned int.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Acked-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/ak881x.c b/drivers/media/video/ak881x.c
index 35390d4..3006a2c 100644
--- a/drivers/media/video/ak881x.c
+++ b/drivers/media/video/ak881x.c
@@ -141,7 +141,7 @@
 	return ak881x_try_g_mbus_fmt(sd, mf);
 }
 
-static int ak881x_enum_mbus_fmt(struct v4l2_subdev *sd, int index,
+static int ak881x_enum_mbus_fmt(struct v4l2_subdev *sd, unsigned int index,
 				enum v4l2_mbus_pixelcode *code)
 {
 	if (index)