ARM: exynos_defconfig: enable platform media drivers

Commit 06b93644

 ("media: Kconfig: add an option to filter in/out
platform drivers") introduced a dependency of all platform media drivers
on the new CONFIG_MEDIA_PLATFORM_SUPPORT symbol, so add it also to
exynos_defconfig. While touching this part, update the media related
configs to the current layout.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>