[llvm] [ADT] Use range-based for loops in StringMap.h (NFC) (PR #152641)

[Jakub Kuderski via llvm-commits]

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@@ -398,8 +401,7 @@ class LLVM_ALLOCATORHOLDER_EMPTYBASE StringMap
 
     // Zap all values, resetting the keys back to non-present (not tombstone),
     // which is safe because we're removing all elements.
-    for (unsigned I = 0, E = NumBuckets; I != E; ++I) {
-      StringMapEntryBase *&Bucket = TheTable[I];
+    for (StringMapEntryBase *&Bucket : buckets()) {
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kuhar wrote:

Do we need this reference? I know the original loop uses that, but I don't see why.

https://github.com/llvm/llvm-project/pull/152641