media: rkisp1: Zero v4l2_subdev_format fields in when validating links

The local sd_fmt variable in rkisp1_capture_link_validate() has
uninitialized fields, which causes random failures when calling the
subdev .get_fmt() operation. Fix it by initializing the variable when
declaring it, which zeros all other fields.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Dafna Hirschfeld <dafna@fastmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/platform/rockchip/rkisp1/rkisp1-capture.c

@@ -1273,11 +1273,12 @@ static int rkisp1_capture_link_validate(struct media_link *link)
 	struct rkisp1_capture *cap = video_get_drvdata(vdev);
 	const struct rkisp1_capture_fmt_cfg *fmt =
 		rkisp1_find_fmt_cfg(cap, cap->pix.fmt.pixelformat);
-	struct v4l2_subdev_format sd_fmt;
+	struct v4l2_subdev_format sd_fmt = {
+		.which = V4L2_SUBDEV_FORMAT_ACTIVE,
+		.pad = link->source->index,
+	};
 	int ret;
 
-	sd_fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
-	sd_fmt.pad = link->source->index;
 	ret = v4l2_subdev_call(sd, pad, get_fmt, NULL, &sd_fmt);
 	if (ret)
 		return ret;