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

unrar: strip out native compilation flag
https://github.com/void-linux/void-packages/pull/50557

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

This should get rid of the native compilation flag in the makefile script.

Not sure if it was included upstream by mistake, but it should be looked out for when new versions are released (ie revert this change if the flag gets removed again).