Update repositories.txt

Arduino library for DAC8574, I2C, 4 channel, 16 bit DAC.

Author: RobTillaart

repositories.txt

@@ -5278,6 +5278,7 @@ https://github.com/RobTillaart/DAC8552
 https://github.com/RobTillaart/DAC8554
 https://github.com/RobTillaart/DAC8560
 https://github.com/RobTillaart/DAC8571
+https://github.com/RobTillaart/DAC8574
 https://github.com/RobTillaart/dateTimeHelpers
 https://github.com/RobTillaart/DEVFULL
 https://github.com/RobTillaart/DEVNULL