glx/egl "multibuffers" denotes if server side support DRI3
multi plane and modifiers which is version >= 1.2. But now
it returns true just when DRI3 version >= 1.
This causes problem when xserver with amdgpu DDX which only
support DRI3 1.0, so "multibuffers" gets set unexpectedly,
and client send DRI3 >= 1.2 request to server which gets
unimplemented error.
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Acked-by: Daniel Stone <daniels@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/31657>