[clang] [clang-format] Add SpaceInParensOption for __attribute__ keyword (PR #77522)

[Owen Pan via cfe-commits]

owenca wrote:

> The __attribute((specifier-list)) currently is formatted based on the SpacesInParensOptions.Other (previously, SpacesInParentheses). This change allows finer control over addition of spaces between the consecutive parens, and between the inner parens and the list of attribute specifiers.
> 
> Differential Revision: https://reviews.llvm.org/D155529
> 
> This is migrated from Phabricator, see more discussion there.

I expressed my opinion there:

> I would have no problem if this new option is extended to handle all double parens, e.g. if (( i = j )), decltype(( x )), etc.

So I still prefer that we have a boolean suboption (e.g. `ConsecutiveParentheses`) that covers all double parens.

https://github.com/llvm/llvm-project/pull/77522