storage/reflink: clarify comment

qubes/storage/reflink.py

@@ -42,9 +42,9 @@ LOGGER = logging.getLogger('qubes.storage.reflink')
 
 
 def _coroutinized(function):
-    ''' Decorator transforming a synchronous function into a coroutine
+    ''' Wrap a synchronous function in a coroutine that runs the
-        that runs the function in the event loop's thread-based
+        function via the event loop's ThreadPool-based default
-        default executor.
+        executor.
     '''
     @asyncio.coroutine
     @functools.wraps(function)