[clang-tools-extra] clang tidy: add header ignore option to include duplicate files (PR #167046)

[Baranov Victor via cfe-commits]

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@@ -33,3 +33,21 @@ Because of the intervening macro definitions, this code remains unchanged:
   #define NDEBUG
   #include "assertion.h"
   // ...code with assertions disabled
+
+Option: ``AllowedDuplicateIncludes``
+------------------------------------
+
+Headers listed in this option are exempt from warnings. For example:
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vbvictor wrote:

Add default value

https://github.com/llvm/llvm-project/pull/167046