[clang] [analyzer][NFC] Cleanup BugType lazy-init patterns (PR #76655)

[Gábor Horváth via cfe-commits]

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@@ -52,10 +52,13 @@ class SimpleStreamChecker : public Checker<check::PostCall,
                                            check::PreCall,
                                            check::DeadSymbols,
                                            check::PointerEscape> {
-  CallDescription OpenFn, CloseFn;
+  const CallDescription OpenFn{{"fopen"}, 2};
+  const CallDescription CloseFn{{"fclose"}, 1};
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Xazax-hun wrote:

Since we mostly use `CallDescription`s with compile time known inputs, it would be nice to make their ctors constexpr. This is not for this PR, just a note for the future.

https://github.com/llvm/llvm-project/pull/76655