minor change to not search in non-existing paths

lib/ansible/utils/plugins.py

@@ -175,6 +175,7 @@ class PluginLoader(object):
 
         found = None
         for path in [p for p in self._get_paths() if p not in self._searched_paths]:
+            if os.path.isdir(path):
                 for potential_file in os.listdir(path):
                     for suffix in suffixes:
                         if potential_file.endswith(suffix):