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

[Aaron Ballman via cfe-commits]

AaronBallman wrote:

> > The current patch actually WILL work with it ONLY enabled on the line inside of the function, which I think is much more intuitive.
> 
> Ooo whoa this is awesome!!

Sorry for the confusion, I've updated the patch summary accordingly

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