Fixed demo example #24

Job	Run time
build (examples/demo)	1m 15s
build (examples/drawExample)	1m 8s
build (examples/drawImages)	1m 9s
build (examples/button)	1m 7s
build (examples/grayscale_test)	1m 10s
build (examples/screen_repair)	1m 7s
build (examples/touch)	1m 16s
build (examples/wifi_sync)	1m 16s
build (examples/spi_driver)	1m 8s
	10m 36s

Provide feedback