Add openlibm to sysimg link line on windows (#53672)
LLVM generates calls to math intrinsics like `trunc` and `rint` (at
least in my local i686 mingw) build, so linking to openlibm is required.
We already have this on the sysimg link line in `Base.link_image`, so
this aligns those options.
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Co-authored-by: Elliot Saba <staticfloat@gmail.com>
