media: dt-bindings: qcom,venus: cleanup

Cleanup the Qualcomm SoC Venus bindings:
 - Drop unneeded blank lines and quotes,
 - Fix indentation in example to 4-space (to match DT schema bindings
   style),
 - Add SoC name in each title.

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>