Travis-CI: Temporarily remove some warnings from the firmware build
Travis-CI: Temporarily remove some warnings from the firmware build

greatscottgadgets/greatfet,dominicgs/GreatFET-experimental,greatscottgadgets/greatfet,dominicgs/GreatFET-experimental,greatscottgadgets/greatfet,greatscottgadgets/greatfet,dominicgs/GreatFET-experimental