[clang] [clang][analyzer] Move checker alpha.unix.StdCLibraryFunctions out of alpha. (PR #66207)

[Balazs Benics via cfe-commits]

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@@ -2651,100 +2745,6 @@ For a more detailed description of configuration options, please see the
 alpha.unix
 ^^^^^^^^^^^
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steakhal wrote:

As we are here, could you align this with its section title as well?

https://github.com/llvm/llvm-project/pull/66207