Replace GPL license statement with SPDX GPL-2.0 license identifier.
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>
Reviewed-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>