sc/nimble_netif: add cmd for diricted advertising
sc/nimble_netif: add cmd for diricted advertising

ant9000/RIOT,jasonatran/RIOT,authmillenon/RIOT,authmillenon/RIOT,RIOT-OS/RIOT,OlegHahm/RIOT,authmillenon/RIOT,miri64/RIOT,kaspar030/RIOT,RIOT-OS/RIOT,kaspar030/RIOT,ant9000/RIOT,OlegHahm/RIOT,kYc0o/RIOT,OlegHahm/RIOT,jasonatran/RIOT,kYc0o/RIOT,kYc0o/RIOT,miri64/RIOT,jasonatran/RIOT,kYc0o/RIOT,ant9000/RIOT,kYc0o/RIOT,ant9000/RIOT,OlegHahm/RIOT,authmillenon/RIOT,jasonatran/RIOT,RIOT-OS/RIOT,ant9000/RIOT,miri64/RIOT,miri64/RIOT,authmillenon/RIOT,kaspar030/RIOT,kaspar030/RIOT,RIOT-OS/RIOT,authmillenon/RIOT,RIOT-OS/RIOT,OlegHahm/RIOT,jasonatran/RIOT,miri64/RIOT,kaspar030/RIOT