[clang] [Clang] Add __ugly__ spelling for the msvc attribute scope (PR #113765)

[Aaron Ballman via cfe-commits]

AaronBallman wrote:

> The MSVC FE team hasn't expressed enthusiasm for adding ugly spellings. If I learn more I'll relay that info.

Thank you for checking! Unfortunately, I think that's a reason for Clang to not support it for the `msvc` vendor prefix either.

https://github.com/llvm/llvm-project/pull/113765