[clang-tools-extra] [clang-tidy] Add user-defined functions to `bugprone-unsafe-functions` check (PR #106350)

[via cfe-commits]

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@@ -19,6 +19,9 @@ The check implements the following rules from the CERT C Coding Standard:
 Unsafe functions
 ----------------
 
+The following functions are reported if `ReportDefaultFunctions
+<unsafe-functions.html#cmdoption-arg-ReportDefaultFunctions>`_ is enabled.
+
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whisperity wrote:

Instead of the automatically generated label which might break apart if the template is changed, try to use a reference label in the RST with a proper identifier and refer that instead.

https://github.com/llvm/llvm-project/pull/106350