drm_hwcomposer: Define cc_defaults for hwc3 binary

Some vendors use drm-hwcomposer by defining and building their own build targets that include both the drm-hwcomposer source and some downstream implementation, such as overriding BufferInfoMapperMetadata::GetFds.

Move the majority of the configuration for the hwc3 service to a cc_defaults target, so that this can be referenced downstream and reduce duplication.