On headless Linux with NVIDIA GPUs and no display server, eglInitialize()
with EGL_DEFAULT_DISPLAY fails with EGL_BAD_ACCESS. The fix falls back to
EGL_EXT_platform_device: enumerate EGL devices and obtain a display via
eglGetPlatformDisplayEXT(EGL_PLATFORM_DEVICE_EXT, ...).
PyOpenGL's egl_get_devices() wrapper doesn't reliably resolve the
eglQueryDevicesEXT function pointer in this scenario, so both functions
are called directly from libEGL.so.1 via ctypes.
Also handles the case where eglInitialize raises EGLError rather than
returning False, which varies by PyOpenGL version and EGL vendor.