drm/i915: Move HAS_RUNTIME_PM definition to platform
Moving all GPU features to the platform struct definition allows for
- standard place when adding new features from new platforms
- possible to see supported features when dumping struct
definitions
Signed-off-by: Carlos Santa <carlos.santa@intel.com> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com> Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>