[clang] [llvm] [clang][ssaf] Add the TUSummaryExtractorRegistry (PR #173290)

[Balázs Benics via cfe-commits]

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@@ -14,128 +14,131 @@
 #define LLVM_SUPPORT_REGISTRY_H
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steakhal wrote:

The diff for this file looks really ugly.
That is almost exclusively due to clang-format. I could split the full reformat of this file into a separate PR, to clean up the diff on this PR is desired.

https://github.com/llvm/llvm-project/pull/173290