[clang] [HLSL][Sema] Validate that occupied register numbers never exceed UINT32_MAX (PR #174028)

[Damyan Pepper via cfe-commits]

================
@@ -2361,6 +2361,99 @@ static bool DiagnoseHLSLRegisterAttribute(Sema &S, SourceLocation &ArgLoc,
   return ValidateMultipleRegisterAnnotations(S, D, RegType);
 }
 
+bool ExceedsUInt32Max(llvm::StringRef S) {
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damyanp wrote:

```suggestion
static bool ExceedsUInt32Max(llvm::StringRef S) {
```

(repeated for all the new functions)

https://github.com/llvm/llvm-project/pull/174028