clang-cl: ignore the /sdl[-] flag

In cl.exe, this flag turns some warnings into errors and adds some
codegen security checks. I don't think we intend to support this.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@192201 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed