net: xfrm statistics depend on INET

net/built-in.o: In function `xfrm_policy_init':
/home/pmundt/devel/git/sh-2.6.25/net/xfrm/xfrm_policy.c:2338: undefined reference to `snmp_mib_init'

snmp_mib_init() is only built in if CONFIG_INET is set.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>