[media] v4l2: integrate support for VIDIOC_QUERY_EXT_CTRL

Add the v4l2 core plumbing for the new VIDIOC_QUERY_EXT_CTRL ioctl.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
diff --git a/include/media/v4l2-ioctl.h b/include/media/v4l2-ioctl.h
index 50cf7c1..53605f0 100644
--- a/include/media/v4l2-ioctl.h
+++ b/include/media/v4l2-ioctl.h
@@ -158,6 +158,8 @@
 		/* Control handling */
 	int (*vidioc_queryctrl)        (struct file *file, void *fh,
 					struct v4l2_queryctrl *a);
+	int (*vidioc_query_ext_ctrl)   (struct file *file, void *fh,
+					struct v4l2_query_ext_ctrl *a);
 	int (*vidioc_g_ctrl)           (struct file *file, void *fh,
 					struct v4l2_control *a);
 	int (*vidioc_s_ctrl)           (struct file *file, void *fh,