[clang] [clang] move -Wcast-function-type under -Wextra (PR #77178)

[Nick Desaulniers via cfe-commits]

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@@ -0,0 +1,42 @@
+// RUN: %clang_cc1 %s -fsyntax-only -Wextra -verify
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nickdesaulniers wrote:

I would just remove the newly created clang/test/Sema/warn-extra-cast-function-type-strict.c.  If you have cases that expose bugs in the implementation, that is distinctly a separate issue from adding this warning under -Wextra.

https://github.com/llvm/llvm-project/pull/77178