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

[Abhin P Jose via cfe-commits]

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

Done. File removed, and a FIXME comment added for the existing test. 

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