[Driver] Accept -fno-lto in clang-cl
Some compiler-rt tests check for the presence of the compiler accepting
-fno-lto to add that flag. Otherwise some tests don't link due to
-flto mismatch between compiling and linking.
$ cmake ... -DLLVM_ENABLE_LTO=Thin ...
$ ninja projects/compiler-rt/lib/sanitizer_common/tests/Sanitizer-x86_64-Test.exe
previously failed, now links.
Reviewed By: hans
Differential Revision: https://reviews.llvm.org/D85252