Don't include gst-omx plugin into Android and iOS list
Don't include gst-omx plugin into Android and iOS list

The list_gstreamer_1_0_plugins_by_category() is only used for these two
platforms and these platforms will never include OMX. As OMX is generic
without being generic, it would be complicated to do the per platform
filter correctly.

https://bugzilla.gnome.org/show_bug.cgi?id=795835

fluendo/cerbero,nirbheek/cerbero,fluendo/cerbero,atsushieno/cerbero,centricular/cerbero,centricular/cerbero,centricular/cerbero,GStreamer/cerbero,atsushieno/cerbero,atsushieno/cerbero,fluendo/cerbero,GStreamer/cerbero,nirbheek/cerbero,atsushieno/cerbero,fluendo/cerbero,centricular/cerbero,GStreamer/cerbero,nirbheek/cerbero,atsushieno/cerbero,fluendo/cerbero,nirbheek/cerbero,GStreamer/cerbero,centricular/cerbero,GStreamer/cerbero