[clang-tools-extra] [clang-tidy] Add fix-its to `avoid-return-with-void-value` check (PR #81420)

[Danny Mösch via cfe-commits]

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@@ -12,14 +12,18 @@ void f2() {
     return f1();
     // CHECK-MESSAGES: :[[@LINE-1]]:5: warning: return statement within a void function should not have a specified return value [readability-avoid-return-with-void-value]
     // CHECK-MESSAGES-LENIENT: :[[@LINE-2]]:5: warning: return statement within a void function should not have a specified return value [readability-avoid-return-with-void-value]
+    // CHECK-FIXES: f1(); return;
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SimplyDanny wrote:

Is an unnecessary `return` okay? Otherwise, this would need an analysis that goes beyond the scope of this rule.

https://github.com/llvm/llvm-project/pull/81420