[clang] [Driver] Add winsysroot alias to the GNU driver (PR #95320)

[Martin Storsjö via cfe-commits]

mstorsjo wrote:

What's the deal with constantly force-pushing an update to the PR, with the exact same contents? With the massive inflow of commits in LLVM, you can't rebase your branch constantly on top of the latest one many times per day, I would say.

And what's going on when #94731 was closed and now this one is reopened?

https://github.com/llvm/llvm-project/pull/95320