[ASan/Win] Add the -Zl flag to avoid /DEFAULTLIB:libcmt directive in the asan_win_uar_thunk object file

This directive results in 'symbol already defined' when linking DLLs that use -MD

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@216663 91177308-0d34-0410-b5e6-96231b3b80d8