[sanitizer] Add macOS minimum deployment target to all compiler invocations in lit tests

The Clang driver on macOS decides the deployment target based on various things, like your host OS version, the SDK version and some environment variables, which makes lit tests pass or fail based on your environment. Let's make sure we run all lit tests with `-mmacosx-version-min=${SANITIZER_MIN_OSX_VERSION}` (10.9 unless overriden).

Differential Revision: https://reviews.llvm.org/D26929

llvm-svn: 288186