[clang] Support MemProf on darwin (PR #69640)

[Teresa Johnson via cfe-commits]

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@@ -78,7 +78,11 @@ static int GetCpuId(void) {
   // will seg fault as the address of __vdso_getcpu will be null.
   if (!memprof_inited)
     return -1;
+#if SANITIZER_APPLE
+  return 0;
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teresajohnson wrote:

If there is a way to do this on Apple then add a FIXME?

https://github.com/llvm/llvm-project/pull/69640