[media] exynos4-is: Add Exynos4x12 FIMC-IS driver

This patch adds a set of core files of the Exynos4x12 FIMC-IS
V4L2 driver. This includes main functionality like allocating
memory, loading the firmware, FIMC-IS register interface and
host CPU <-> IS command and error code definitions.
The driver currently exposes a single subdev named FIMC-IS-ISP,
which corresponds to the FIMC-IS ISP and DRC IP blocks.
The FIMC-IS-ISP subdev currently supports only a subset of user
controls. For other controls we need several extensions at the
V4L2 API. The supported standard controls are:
brightness, contrast, saturation, hue, sharpness, 3a_lock,
exposure_time_absolute, white_balance_auto_preset,
iso_sensitivity, iso_sensitivity_auto, exposure_metering_mode.

Signed-off-by: Younghwan Joo <yhwan.joo@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>