There's a merged pull request on the void-packages repository

wayland: update to 0.19.0, adopt.
https://github.com/void-linux/void-packages/pull/28296

Description:
Also fix ndebug mode with meson options instead of CFLAGS.

I don't know why `-UNDEBUG` was initially added, though. In 0f7885c6d61c2814c98420e6791885c02280a981 it isn't explained.

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- [x] I use the packages affected by the proposed changes on a regular basis and confirm this PR works for me (though I haven't gone through extensive testing)
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