[clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Cyndy Ishida via cfe-commits]

cyndyishida wrote:

> FYI, it looks like this change broke `compiler-rt` build, e.g. in https://lab.llvm.org/buildbot/#/builders/270/builds/12485

Should be resolved by: https://github.com/llvm/llvm-project/commit/fe45029dbdee6b3df2dbeaed17c9dd598ec511f2 
I suspect compiler-rt may be relying on defaults set by Apple* cmake caches on unrelated environments.

https://github.com/llvm/llvm-project/pull/87684