In theory, this should prevent the BIOS from requesting them from us, and
this should be the right thing.

In practice, this is not always the case, and might surprise the BIOS.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>