color: rely on H.273 CICP
This deletes the primaries enumeration, and transfer function enumeration we didn't even have anymore. Instead, we rely on H.273 CICP enumerations.
Advertisement events are added for CICP values for TransferCharacteristics and ColourPrimaries. This allows H.273 to be extended without breaking us, and makes it explicit what compositors support.
Finally, some rewording for the set_tf_gamma and set_primaries requests, and add a forgotten error code for an already set property.