The wlroots Wayland backend does not support gamma LUT application and
will currently fail to render anything if river commits a gamma LUT.
To fix this, test the state when applying a gamma LUT and fall back to a
state with no gamma LUT set if that fails.
This problem was revealed by 2e09b66 which flags gamma as dirty on all
outputs when they are enabled.
(cherry picked from commit a80e0f7322b1f9f8b091a327aaea366b615042c8)
