[clang] [clang][PAC] add support for options parameter to __ptrauth (PR #136828)

[Oliver Hunt via cfe-commits]

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@@ -327,6 +330,27 @@ a discriminator determined as follows:
   is ``ptrauth_blend_discriminator(&x, discriminator)``; see
   `ptrauth_blend_discriminator`_.
 
+``ptrauth_qualifier_options``
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The options parameter to the ``__ptrauth`` qualifier is a string of comma
+separated modifiers to the normal authentication behavior. Currently supported
+options are
+
+- Authentication mode: This is one of ``strip``, ``sign-and-strip``, and
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ojhunt wrote:

This PR does not actually provide the implementation of this option, as it touches a number of places unrelated to parsing the option.

https://github.com/llvm/llvm-project/pull/136828