This is an ABI break, in that we now pass NULL to a function that hasn't
accepted it before.
Alex Goins had a different patch for this but it wasn't symmetrical, it
freed something in a very different place than it allocated it, this
attempts to retain symmetry in the releasing of the backing bo.
v2: use a new toplevel API, though it still passes NULL to something
that wasn't expecting it.
v3: pass -1 instead of 0.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Alex Goins <agoins at nvidia.com>