Add dylib-has-no-filesystem when filesystem is disabled

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@356640 91177308-0d34-0410-b5e6-96231b3b80d8

utils/libcxx/test/config.py

@@ -437,6 +437,8 @@ class Configuration(object):
 
         if not self.get_lit_bool('enable_filesystem', default=True):
             self.config.available_features.add('c++filesystem-disabled')
+            self.config.available_features.add('dylib-has-no-filesystem')
+
 
         # Run a compile test for the -fsized-deallocation flag. This is needed
         # in test/std/language.support/support.dynamic/new.delete