Fix gstreamer-vaapi includedir for GStreamer 1.2 setups. i.e. use
the pkgconfig version (1.0) instead of the intended API version (1.2).
libgstvaapi1.0-dev and libgstvaapi1.2-dev packages will now conflict,
as would core GStreamer 1.0 and GStreamer 1.2 dev packages anyway.
Fix the pluginsdir and includedir variables in the generated pkgconfig
(.pc) files. The location needs to be built with the PKG version in
mind instead of the API version.
While we are at it, also fix the PKG version for GStreamer >= 1.3.
https://bugzilla.gnome.org/show_bug.cgi?id=720820
[additional fixes for includedir and pkg requirements]
Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>
