Document Airplay2 change
+202107xx:
+- New Shairport version with Airplay2 support
+- Linux kernel upgraded to 5.10
+- Bugfix: Incorrect detection of clocks on DAC+ Pro and DAC2 Pro
+- Bugfix: Some actions for Interact missingy
+
20210531:
- Remap interrupt pin for power controller (requires update of power controller firmware)
- audiocontrol improvements
