[PM] Fix up from r290449 to start requiring the x86 target to be available.
[PM] Fix up from r290449 to start requiring the x86 target to be
available.

It doesn't seem terribly important to test this with a specific target
triple but without that target available.

git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@290451 91177308-0d34-0410-b5e6-96231b3b80d8

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