Add support for PVR_RECORDING.iChannelUid

[ksooo]

Please add support for PVR_RECORDING.iChannelUid. Although PVR Addon API declares this property as optional, some Kodi features cannot work if the channel uid is not given with a recording, namely the "red dot" indicating an in-progress recording in pvr recordings window and recently recorded home screen widget, the right context menu entries for recordings in progess, maybe others.

Unfortunately, there is no reliable fix in Kodi possible without an PVR addon API change (which I plan for Kodi v19, btw.).

Thus, I kindly ask the maintainer of this addon or anybody else with the needed skills to add support for PVR_RECORDING.iChannelUid so we can fix the above mentioned issues for Kodi v18.

Thanks.