Fix Generic_GCC::GCCVersion::operator<
Fix Generic_GCC::GCCVersion::operator<

Without this patch comparing two equal versions without patch numbers (4.7 for
example) will result in A < B and B < A.

Patch by Simon Atanasyan.

git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@170705 91177308-0d34-0410-b5e6-96231b3b80d8

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