Take one more free bit to indicate it's IDR vs. internal
usage, to be able to carve out some bits here for other
internal usage, other than IDR handling with a full ACK
SKB, that is.
Reviewed-by: Benjamin Berg <benjamin.berg@intel.com>
Reviewed-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>