[clang] [clang] Implement -Wmissing-include-dirs (PR #94827)

[Jim Colerick via cfe-commits]

invlpg wrote:

> Implements -Wmissing-include-dirs #92015
> 
> This is my first contribution and would love some feedback. Thanks

lgtm 👍 

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```

https://github.com/llvm/llvm-project/pull/94827