[clang] Control analysis-based diagnostics with #pragma (PR #136323)

[via cfe-commits]

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@@ -1202,6 +1202,30 @@ Clang also allows you to push and pop the current warning state. This is
 particularly useful when writing a header file that will be compiled by
 other people, because you don't know what warning flags they build with.
 
+Note that the following diagnostic groups, which are ones based on analyzing
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cor3ntin wrote:

Alternatively, maybe we can detect and diagnose `#pragma clang diagnostic` inside a function being analyzed and warn that it's ignored

https://github.com/llvm/llvm-project/pull/136323