media: core: v4l2-ioctl.c: use is_valid_ioctl()

In most cases the is_valid_ioctl() macro is used to check if an ioctl is
valid, except in one place. Use it there as well as it makes the code
easier to read.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index 33076af..6e7b8b6 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -3028,7 +3028,7 @@ static long __video_do_ioctl(struct file *file,
 	if (v4l2_is_known_ioctl(cmd)) {
 		info = &v4l2_ioctls[_IOC_NR(cmd)];
 
-		if (!test_bit(_IOC_NR(cmd), vfd->valid_ioctls) &&
+		if (!is_valid_ioctl(vfd, cmd) &&
 		    !((info->flags & INFO_FL_CTRL) && vfh && vfh->ctrl_handler))
 			goto done;