Fixed setBrightness https://github.com/Xinyuan-LilyGO/T-Display-S3/is… #141

Job	Run time
build (Arduino_GFXDemo)	1m 19s
build (Arduino_GFX_PDQgraphicstest)	1m 27s
build (GetBatteryVoltage)	1m 6s
build (I2CScan)	1m 11s
build (ImageScroll)	1m 12s
build (MPR121TouchSensor)	3m 30s
build (PCBClock)	1m 11s
build (PokerS3)	1m 15s
build (SerialExample)	1m 9s
build (T-Display-S3-MIDI)	1m 24s
build (TFT_Rainbow)	1m 12s
build (factory)	1m 21s
build (lv_demos)	1m 22s
build (nes)	1m 37s
build (ota)	1m 9s
build (sd)	1m 17s
build (tft)	1m 13s
build (touch_test)	1m 13s
build (usb_hid_pad)	1m 16s
	26m 24s

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