Convert the Samsung SoC JPEG codec bindings to DT schema.

The original bindings were quite old and incomplete, so change during
conversion:
1. Add typical (already used) properties like iommus and power domains.
2. Document samsung,exynos4212-jpeg compatible (already used in DTS and
   driver).
3. List clocks per each variant.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>