Fix https://issues.dlang.org/show_bug.cgi?id=24546 for musl libc

[JohanEngelen]

No description provided.

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	24546	major	importC musl setjmp.h failure

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "stable + dmd#16507"

[dkorpel]

I've changed the commit message so the bot picks it up

[JohanEngelen]

CI seems to be stuck