Use Itanium triple in test using -Wpadding
Use Itanium triple in test using -Wpadding

-Wpadding is not implemented in the Microsoft record layout builder.
This test only passes on Windows because PCH forces us to use the
Itanium record layout builder. I'm about to fix that, so change the
test to not rely on that ridiculous behavior.

git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@230524 91177308-0d34-0410-b5e6-96231b3b80d8

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