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

[Dan Liew via cfe-commits]

================
@@ -654,6 +654,11 @@ enabled sub-projects. Nearly all of these variable names begin with
   Generate dSYM files and strip executables and libraries (Darwin Only).
   Defaults to OFF.
 
+**LLVM_ENABLE_EXPORTED_SYMBOLS**:BOOL
+  When building executables, preserve symbol exports. Defaults to ON. 
+  You can use this option to disable exported symbols on all executable build
----------------
delcypher wrote:

```suggestion
  Setting this option to ``OFF`` removes exported symbols from all executables.
```

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