Revert "Restrict COFF to a single thread when symbol count is high (#50874)" (#59736)
This reverts commit eb4416b16b8a865376da5c76451a4d60516e2c4a.
As of LLVM 16, we automatically emit:
```
.drectve `-exclude-symbols:"<symbol>"`
```
which mitigates this issue where it is supported by the linker (GCC 11+
and LLD 14+ are tested working)
PackageCompiler on Windows now ships GCC 14
(https://github.com/JuliaLang/PackageCompiler.jl/pull/1012), so we
should no longer need this workaround that can make a 15-minute sysimage
compilation take an hour+
(cherry picked from commit 1cba9c292c6bad490cca49cd52e333632a3fab91)