DAC Exported Constants

Modules
	DAC flags
	Flags defines which can be used with LL_DAC_ReadReg function.
	DAC interruptions
	IT defines which can be used with LL_DAC_ReadReg and LL_DAC_WriteReg functions.
	DAC channels
	DAC trigger source
	DAC waveform automatic generation mode
	DAC wave generation - Noise LFSR unmask bits
	DAC wave generation - Triangle amplitude
	DAC channel output buffer
	DAC channel output resolution
	DAC registers compliant with specific purpose
	Definitions of DAC hardware constraints delays