Backport #10616: OpenBSD --strip-unneeded strips too much

[mergify]

Brought to our attention by maerwald; see https://cvsweb.openbsd.org/cgi-bin/cvsweb/~checkout~/ports/lang/ghc/patches/patch-libraries_Cabal_Cabal_Distribution_Simple_Program_Strip_hs.

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This is an automatic backport of pull request #10616 done by [Mergify](https://mergify.com).