When sharing DMA-BUFs it is required the announce the underlying
hardware capabilities via supported modifiers.
Add new device_query_dmabuf_capabilities vfunc to gs_exports and connect it
to the egl implementation stubs in the supported render platforms. Add a new
public method gs_query_dmabuf_capabilities() that calls the vfunc above.
Add new device_query_dmabuf_modifiers vfunc to gs_exports and connect it
to the egl implementation in the supported render platforms. Add a new
public method gs_query_dmabuf_modifiers() that calls the vfunc above.
4cda05f270