[llvm] [ADT] [NFC] Resolve a potential overload ambiguity in the ADT unit tests (PR #85341)

[Simon Pilgrim via llvm-commits]

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@@ -2918,7 +2918,7 @@ TEST(APIntTest, Average) {
   APInt A100(32, 100);
   APInt A101(32, 101);
   APInt A200(32, 200, false);
-  APInt ApUMax(32, UINT_MAX, false);
+  APInt ApUMax(32, static_cast<uint64_t>(UINT_MAX), false);
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RKSimon wrote:

This would be my preferred option:
```cpp
APInt ApUMax = APInt::getMaxValue(32);
```

https://github.com/llvm/llvm-project/pull/85341