[X86] Make x86-intrinsics-headers-clean.cpp stricter.
[X86] Make x86-intrinsics-headers-clean.cpp stricter.

Remove the -Wno-ignored-attributes.

Add -fno-lax-vector-conversions

Also use -ffreestanding instead of defining _MM_MALLOC_H.

git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@355659 91177308-0d34-0410-b5e6-96231b3b80d8

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