egl/dri2: Dispatch eglCreateWaylandBufferFromImageWL by display, not driver

Add dri2_egl_display_vtbl::create_wayland_buffer_from_image, set it for
each platform, and let egl_dri2 dispatch
eglCreateWaylandBufferFromImageWL to that.

This prepares for the EGL platform extensions.

Signed-off-by: Chad Versace <chad.versace@linux.intel.com>
7 files changed