The commit 4bc1796b34 had incorrect
calculation of the session lists minimal timeout, resulting
in returned value of 0 which resulted in existing sessions
constantly requeued, taking up the CPU. Fix this calculation.
Change-Id: I9a789739f96a1f01522c68f91b0a02db2417837f
Signed-off-by: Andrew Yourtchenko <ayourtch@gmail.com>