config: add OMX.Aratelia.video_decoder.vp8 to Tizonia config
config: add OMX.Aratelia.video_decoder.vp8 to Tizonia config

Useful mostly for testing/debugging purpose as this is a software
based encoder (libvpxdec) for which GStreamer provides a direct
wrapper.

https://bugzilla.gnome.org/show_bug.cgi?id=783976

CapOM/gst-omx,CapOM/gst-omx,CapOM/gst-omx,GStreamer/gst-omx,GStreamer/gst-omx,GStreamer/gst-omx