Get current display brightness of the screen.
Return value: uint8_t status
Current display brightness setting
0x01 AutoDisplayBrightness_Enable
0x02 AutoDisplayBrightness_Disable_medium
0x03 AutoDisplayBrightness_Disable_dimmest
0x04 AutoDisplayBrightness_Disable_dim
0x05 AutoDisplayBrightness_Disable_bright
0x06 AutoDisplayBrightness_Disable_brightest
If value 0x01 is returned, then display brightness is set to enable. i.e AutoDisplayBrightness_Enable.