[clang-tools-extra] [clang-doc] Add HTMLMustacheGenerator.cpp (PR #138060)

[Daniel Thornburgh via cfe-commits]

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@@ -0,0 +1,85 @@
+//===-- HTMLMustacheGenerator.cpp - HTML Mustache Generator -----*- C++ -*-===//
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mysterymath wrote:

Nit: the C++ tag is no longer needed.

https://github.com/llvm/llvm-project/pull/138060