[llvm] [BOLT] Fix runOnEachFunctionWithUniqueAllocId (PR #90039)

[Maksim Panchenko via llvm-commits]

================
@@ -164,6 +164,15 @@ void runOnEachFunction(BinaryContext &BC, SchedulingPolicy SchedPolicy,
   Pool.wait();
 }
 
+static void EnsureAllocatorExists(BinaryContext &BC, unsigned AllocId) {
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maksfb wrote:

```suggestion
static void ensureAllocatorExists(BinaryContext &BC, unsigned AllocId) {
```

https://github.com/llvm/llvm-project/pull/90039