build: check eglext.h header version
We use EGL_EXT_device_drm_render_node, which has been introduced here: https://github.com/KhronosGroup/EGL-Registry/commit/53f038f6fd43e25d8d20f2688f5500b3079e9f25
Due to an influx of spam, we have had to impose restrictions on new accounts. Please see this wiki page for instructions on how to get full permissions. Sorry for the inconvenience.
We use EGL_EXT_device_drm_render_node, which has been introduced here: https://github.com/KhronosGroup/EGL-Registry/commit/53f038f6fd43e25d8d20f2688f5500b3079e9f25