tests/periph_rtt_min: update CPUs with configurable rtt freq
tests/periph_rtt_min: update CPUs with configurable rtt freq

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