Remove a warning message.

Its normal on our platform now.

Fixes b/17663720

Change-Id: I9bff9c4a5fbf20a67be95bac5fc5d729f685745e
diff --git a/tornado/ioloop.py b/tornado/ioloop.py
index 6507c06..49b9c15 100644
--- a/tornado/ioloop.py
+++ b/tornado/ioloop.py
@@ -686,6 +686,4 @@
     except Exception:
         # All other systems
         import sys
-        if "linux" in sys.platform:
-            logging.warning("epoll module not found; using select()")
         _poll = _Select