[llvm] [NFC][CodingStandard] Add additional example for if-else brace rule (PR #111733)

[Rahul Joshi via llvm-commits]

jurahul wrote:

> I see this example as covering what the text already states:
> 
> > readability is also harmed if an `if`/`else` chain does not use braced bodies for either all or none of its members
> 
> The example sections is meant to illustrate the text, so LGTM here.

Agreed. The example is meant as additional reinforcement as the first instinct might be to look at examples, and since this one is commonly violated, would help with an example.

I'll let the thread sit for a week or 2 and if there are no concerns raised, we can commit this PR.

https://github.com/llvm/llvm-project/pull/111733