media: v4l: async: Don't check whether asd is NULL in validity check

The callers do pass a non-NULL asd to v4l2_async_nf_asd_valid() already.
There's no need for the NULL check here.
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/v4l2-core/v4l2-async.c

@@ -554,9 +554,6 @@ static int v4l2_async_nf_asd_valid(struct v4l2_async_notifier *notifier,
 {
 	struct device *dev = notifier_dev(notifier);
 
-	if (!asd)
-		return -EINVAL;
-
 	switch (asd->match_type) {
 	case V4L2_ASYNC_MATCH_I2C:
 	case V4L2_ASYNC_MATCH_FWNODE: