Use WARN_ONCE in a bunch of places and demote a message that would
continually spam us.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: NDamien Lespiau <damien.lespiau@intel.com>
Acked-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>