[clang-format] Wildcard expansion on Windows.

Summary:
Add support for wildcard expansion in command line arguments on Windows.
See https://docs.microsoft.com/en-us/cpp/c-language/expanding-wildcard-arguments

Fixes https://bugs.llvm.org/show_bug.cgi?id=17217

Reviewers: klimek, djasper, rnk

Reviewed By: rnk

Subscribers: rnk, smeenai, zturner, alexfh, mgorny, cfe-commits

Differential Revision: https://reviews.llvm.org/D44778

llvm-svn: 328495