do not write config on exit, only on config changes

git-svn-id: svn://bind10.isc.org/svn/bind10/branches/trac435@3964 e5f2f494-b856-4b98-b285-d166d9295462

src/bin/cfgmgr/b10-cfgmgr.py.in

@@ -61,8 +61,6 @@ def main():
     except ConfigManagerDataReadError as cmdre:
         print("[b10-cfgmgr] " + str(cmdre))
         return 2
-    if cm:
-        return cm.write_config()
     return 0
 
 if __name__ == "__main__":