Split render/display setups have two separate devices: one display-only
with a primary node, and one render-only with a render node. However
in these cases the EGL implementation and the Wayland compositor will
advertise the display device instead of the render device [1]. The EGL
implementation will magically open the render device when the display
device is passed in.
So just pass the display device as if it were a render device. Maybe in
the future Mesa will advertise the render device instead and we'll be
able to remove this workaround.
[1]: https://gitlab.freedesktop.org/mesa/mesa/-/issues/4178
b89bcffea4