ext/ffmpeg/gstffmpegcolorspace.c: Backport changes from ffmpegcolorspace (gst-plugins) so we can then move the whole ...

Original commit message from CVS:
* ext/ffmpeg/gstffmpegcolorspace.c: (gst_ffmpegcsp_pad_link):
Backport changes from ffmpegcolorspace (gst-plugins) so we can
then move the whole of this plugin back and deprecate this (no,
I'm not insane).