[llvm] Remove -Wl, -z, defs linker flag when building shared libraries using llvm with emscripten (PR #123396)

[Vassil Vassilev via llvm-commits]

https://github.com/vgvassilev commented:

Perhaps @sbc100 is one of the people who could tell if that makes sense...

https://github.com/llvm/llvm-project/pull/123396