egl/wayland: Implement DRI_PRIME support

egl/wayland: Implement DRI_PRIME support

When the server gpu and requested gpu are different:
. They likely don't support the same tiling modes
. They likely do not have fast access to the same locations

Thus we do:
. render to a tiled buffer we do not share with the server
. Copy the content at every swap to a buffer with no tiling
that we share with the server.

This is similar to the glx dri3 DRI_PRIME implementation.

Reviewed-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Signed-off-by: Axel Davy <axel.davy@ens.fr>