[clang] Reland "[Win32][ELF] Make CodeView a DebugInfoFormat only for COFF format", second try (PR #88245)

[Fangrui Song via cfe-commits]

MaskRay wrote:

For driver tests we prefer specifying a concrete target triple than making a test dependent on the default target triple (controlled by `REQUIES: coff-supported-target` in this case).

A concrete target triple (e.g. x86_64-windows) loses coverage for aarch64-windows, but we generally accept the loss.

https://github.com/llvm/llvm-project/pull/88245