Release 1.8.4 with Wayland fixes

Hi,

in the next few months we would like to release Kodi with native Wayland support. libva-1 is sadly broken on Wayland in all currently available public releases as the only release that includes fixes is 2.0.0. Realistically though, we cannot expect all current distributions to immediately jump to libva-2 as it would lead to recompilation of lots of packages because of the API/ABI changes - so we cannot depend on libva-2 in Kodi.

Instead, it would be nice to have the following patches applied in a public release of the libva-1 series (they should all apply cleanly to 1.8.3 I think) so we could depend on that:
* https://github.com/01org/libva/pull/98
* https://github.com/01org/libva/pull/65
* https://github.com/01org/libva/pull/67
* https://github.com/01org/libva/pull/66

The first two are absolutely necessary, the other two are nice-to-have. It really should not be a lot of work so I'm hoping for a positive reply :-) Feel free to ask if you need more information on the issues we're facing.

cc @wsnipex