build: fix a condition inversion in git-based versioning
build: fix a condition inversion in git-based versioning

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