[media] gscaler: Add core functionality for the G-Scaler driver

This patch adds the core functionality for the G-Scaler driver.
Signed-off-by: Hynwoong Kim <khw0178.kim@samsung.com>
Signed-off-by: Sungchun Kang <sungchun.kang@samsung.com>
Signed-off-by: Shaik Ameer Basha <shaik.ameer@samsung.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>