If called without ip_set.ko loaded, the unconditional 'rmmod ip_set' at
startup will fail and the previous 'set -e' makes that fatal.
Fixes: ed47b815a0d2c ("tests: add namespace test and take into account delayed set removal at module remove") Signed-off-by: Phil Sutter <phil@nwl.cc> Acked-by: Jozsef Kadlecsik <kadlec@netfilter.org>