CBQE-2322 fix error global name 'WIN_TMP_PATH' is not defined
on windows failover test

Change-Id: I00b5ddbf8d7340eb668b79f1fce6bc38baa5aad7
Reviewed-on: http://review.couchbase.org/39299
Reviewed-by: Thuan Nguyen <soccon@gmail.com>
Tested-by: Thuan Nguyen <soccon@gmail.com>