[PATCH] [libcxx] Set -D_LIBCPP_HAS_NO_THREADS and -D_LIBCPP_HAS_NO_MONOTONIC_CLOCK based on available_features

[Dan Albert]

================
Comment at: lit.cfg:296
@@ +295,3 @@
+        for f in additional_features:
+            self.config.available_features.add(f)
+
----------------
Probably f.strip() to be safe. I don't know what lit would do with --param=additional_features=' foo,   bar'

http://reviews.llvm.org/D5214