[clang] [NFC][rtsan] Docs of how to disable rtsan (PR #107707)

[via cfe-commits]

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@@ -83,3 +83,53 @@ non-zero exit code.
     #13 0x00010230dd64 in main main.cpp:9
     #14 0x0001958960dc  (<unknown module>)
     #15 0x2f557ffffffffffc  (<unknown module>)
+
+Disabling
+---------
+
+In some circumstances, you may want to suppress RealtimeSanitizer violations in a specific scope.
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davidtrevelyan wrote:

Minor nit: it's not technically the violations that are suppressed, it's the error messages and action invoked on detecting a violation. I appreciate this is a bit "if a tree falls in a forest, does it make a sound?", but I reckon it's worth clarifying. My suggestion would be to re-word this (and the one on line 92) like "you may want to suppress RealtimeSanitizer errors in a specific scope"

https://github.com/llvm/llvm-project/pull/107707