media: ar0521: Remove redundant variable ret

ret in ar0521_set_fmt is never set to values other than 0. Replace it with
plain 0.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/i2c/ar0521.c

@@ -406,7 +406,6 @@ static int ar0521_set_fmt(struct v4l2_subdev *sd,
 			  struct v4l2_subdev_format *format)
 {
 	struct ar0521_dev *sensor = to_ar0521_dev(sd);
-	int ret = 0;
 
 	ar0521_adj_fmt(&format->format);
 
@@ -423,7 +422,7 @@ static int ar0521_set_fmt(struct v4l2_subdev *sd,
 	}
 
 	mutex_unlock(&sensor->lock);
-	return ret;
+	return 0;
 }
 
 static int ar0521_s_ctrl(struct v4l2_ctrl *ctrl)