clang/test/lit.cfg: Disable dev-fd-fs on cygwin for now.
clang/test/lit.cfg: Disable dev-fd-fs on cygwin for now.

open("/dev/fd/1-foobar") fails with EEXIST on cygwin.

git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@168676 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang