some tvg-id are empty in the upstream source

[kl0wn]

in some cases the tvg-id is empty which means there is no channel name to match on. However there is always the actual "display name" this isn't great, but we could potentially look to scope up the "display name" and then postfix a .undefined as part of the tvg-id the only danger is that we could have channel name collisions across different countries etc.