sys/architecture: add comment on pronunciation
sys/architecture: add comment on pronunciation

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