[IPVS]: Relax the module get/put in ip_vs_app.c

Both try_module_get/module_put already handle the module == NULL
case, so no need in manual checking.

This patch fits both net-2.6 and net-2.6.25.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>