First part for P2P support. It is a variation on the existing
scanning functionality and is used to discover peer-to-peer
group owners and/or peer-to-peer devices in listen state.

Tested with wpa_cli/wpa_supplicant v2.0-devel.
Reviewed-by: NPieter-Paul Giesberts <pieterpg@broadcom.com>
Reviewed-by: NHante Meuleman <meuleman@broadcom.com>
Signed-off-by: NArend van Spriel <arend@broadcom.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>