[media] exynos-gsc: Fix settings for input and output image RGB type

Macros used to set input and output RGB type aren't correct.
Updating the macros as per register manual.

Signed-off-by: Shaik Ameer Basha <shaik.ameer@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>