[libc-commits] [libc] [libc] Replace `MutexLock` with `cpp::lock_guard` (PR #89340)

[Nick Desaulniers via libc-commits]

================
@@ -8,6 +8,7 @@
 
 #include "fork_callbacks.h"
 
+#include "src/__support/CPP/mutex.h" // For lock_guard
----------------
nickdesaulniers wrote:

```suggestion
#include "src/__support/CPP/mutex.h" // lock_guard
```

https://github.com/llvm/llvm-project/pull/89340