[omxplayer] Use display time for EDL cut start time

There are reports that EDL commercial break skipping occurs 5-10 seconds too early. This is because the skip occurs when a timestamp
is received at PlayerVideo/PlayerAudio, but it may still be a number of seconds before that frame is presented by the GPU.

Instead use the display time (GetTime) to determine start of cut time
[omxplayer] Don't fail to open a stream with zero dimensions

The fast channel switching mod means OMXVideo may be opened before hints.width/hints/width is valid.
If we fail here, we do get opened again when the width/height are available, but we have already skipped
some init code like openeing the EDL files. Behave more like dvdplayer and ignore the zero dimensions.
[omxplayer] Avoid choosing TrueHD as default audio track

The Pi cannot decode TrueHD audio successfully, so make the default audio avoid choosing that.
It can still be switched to manually
[rbp] Disable unsupport HD audio passthrough options

The hardware can't support HD audio, so remove them from settings
[PiSink] Set hdmi stream channels when in passthrough mode

The GPU needs to know when in passthrough mode to set the number of channels
in the AV info frame to "refer to stream", so let it know.

This fixes AC3/DTS passthrough with Pi Sink. (Needs recent firmware).
[rbp] Report in log if MPEG2 and VC1 licences are enabled

A frequent support question is whether mpeg2/vc1 licences have been enabled correctly.
Put that info in log.
Merge pull request #4148 from popcornmix/streamchannels

[PiSink] Set hdmi stream channels when in passthrough mode
Merge pull request #4144 from popcornmix/edl_fixes

[omxplayer] EDL fixes for omxplayer
Merge pull request #4145 from popcornmix/truhd

[omxplayer] Avoid choosing TrueHD as default audio track
Merge pull request #4146 from popcornmix/unsupported_settings

[rbp] Disable unsupport HD audio passthrough options
Merge pull request #4149 from popcornmix/report_licence

[rbp] Report in log if MPEG2 and VC1 licences are enabled