exynos-gsc: Do not swap cb/cr for semi planar formats

[ Upstream commit d7f3e33df4fbdc9855fb151f4a328ec46447e3ba ]

In the case of semi planar formats cb and cr are in the same plane
in memory, meaning that will be set to 'cb' whatever the format is,
and whatever the (packed) order of those components are.

Suggested-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Signed-off-by: Thibault Saunier <thibault.saunier@osg.samsung.com>
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>