[llvm] [Bazel] Fix Host target's exported headers to include windows (PR #213018)

[Jordan Rupprecht via llvm-commits]

https://github.com/rupprecht approved this pull request.

huh, the ConPTYUtils.h situation in LLDB seems weird. Seems like a windows-specific utility that doesn't belong in the common host library.

https://github.com/llvm/llvm-project/pull/213018