[clang-tools-extra] [llvm] New check `misc-header-guard` (PR #177315)

[Baranov Victor via cfe-commits]

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@@ -0,0 +1,90 @@
+.. title:: clang-tidy - llvm-header-guard
+
+misc-header-guard
+=================
+
+Finds and fixes header guards.
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vbvictor wrote:

Yeah, I understand. For LLVM-style we have description in https://llvm.org/docs/CodingStandards.html#header-guard about how headers should look like.
But for general audience we should be verbose about what check does.

https://github.com/llvm/llvm-project/pull/177315