wip: use the glx-to-egl adaptor outside of just Xwayland
We're still using magic dlsyms into the DRI driver to set up GLX, even though when we're using glamor there's a perfectly good window system and GL we could set this up from instead. Possible wins here:
-
modesetting driver using egl adaptor -
Xephyr ported to EGL and using adaptor -
EGL adaptor taught how to do indirect GLX -
Factor out enough from EGL adaptor to be usable without glamor