[media] media: am437x-vpfe: Requested frame size and fmt overwritten by current sensor setting

Upon a S_FMT the input/requested frame size and pixel format is
overwritten by the current sub-device settings.
Fix this so application can actually set the frame size and format.

Fixes: 417d2e50 ("[media] media: platform: add VPFE capture driver support for AM437X")

Cc: <stable@vger.kernel.org> # v4.0+
Signed-off-by: Benoit Parrot <bparrot@ti.com>
Acked-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/platform/am437x/am437x-vpfe.c

@@ -1565,7 +1565,7 @@ static int vpfe_s_fmt(struct file *file, void *priv,
 		return -EBUSY;
 	}
 
-	ret = vpfe_try_fmt(file, priv, fmt);
+	ret = vpfe_try_fmt(file, priv, &format);
 	if (ret)
 		return ret;