adds 9x6 font to switch, adds make commands

Makefile

@@ -1 +1,9 @@
+setup:
+	cd go-rpi-rgb-led-matrix/lib/rpi-rgb-led-matrix
+	make
 
+run:
+	sudo go run cmd/rpi/main.go --led-slowdown-gpio=2
+
+build:
+	go build cmd/rpi/main.go

display/slot.go

@@ -66,6 +66,8 @@ func (s *Slot) Update(text []Segment) error {
 		font = fonts.Face5x4
 	case 7:
 		font = fonts.Face7x5
+	case 9:
+		font = fonts.Face9x6
 	default:
 		return fmt.Errorf("%w: %d", ErrUnsupportedSlotHeight, s.segmentHeight)
 	}