Switch gamma control to wlr-gamma-control-unstable-v1
The old protocol has a few issues. The new one is here:
https://github.com/swaywm/wlr-protocols/blob/master/unstable/wlr-gamma-control-unstable-v1.xml
The old protocol has a few issues. The new one is here:
https://github.com/swaywm/wlr-protocols/blob/master/unstable/wlr-gamma-control-unstable-v1.xml