Remove sys unused

This is patch remove sys import unused in
doc/source/conf.py

Change-Id: Ifc0f8e6c6dd2e37e207d7118bad1d90f18c40028
diff --git a/doc/source/conf.py b/doc/source/conf.py
index 2edaddb..9372d32 100644
--- a/doc/source/conf.py
+++ b/doc/source/conf.py
@@ -11,7 +11,6 @@
 # All configuration values have a default; values that are commented out
 # serve to show the default.
 
-import sys
 import os
 import subprocess
 import warnings