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

kanshi: add dependency on libvarlink to enable building kanshictl
https://github.com/void-linux/void-packages/pull/40914

Description:
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The most recent release of kanshi added an optional kanshictl utility, which
uses varlink. If libvarlink-devel is available at build time, meson will
automatically enable that functionality and provide both the binary and the man
page for it.

#### Testing the changes
- I tested the changes in this PR: **YES**

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