wl_drm is the legacy protocol which is used to support
EGL_WL_bind_wayland_display to exchange buffers between client and
server. It's supported dmabuf for a very long time, and as a private
protocol for Mesa's use, there is no need to carry around support for
old codepaths, as all relevant drivers support dmabuf.
Signed-off-by: Daniel Stone <daniels@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/35885>