iptables 1.6.2 fails without /run, because it tries to create
the /run/xtables.lock file

Test output: ================================
Fatal: can't open lock file /run/xtables.lock: No such file or directory
23:29:06.098:     4: ERR: netns-nf.c:21: Can't set input rule (errno = 2 (No such file or directory))
23:29:06.098:     3: ERR: test.c:315: Test exited unexpectedly with code 255
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>