media: dt-bindings: samsung,fimc: convert to dtschema

Convert the Samsung S5P/Exynos Camera Subsystem (FIMC) bindings to DT
schema.  Changes during conversion - adjust to existing DTS and Linux
driver: add iommus and power-domains.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>