Fixed oops after failed netlink socket creation.

Wrong parathenses in if() statement caused err to be 1,
instead of negative value.

Trivial fix, not trivial to find though.
Signed-Off-By: NDmitry Mishin <dim@sw.ru>
Signed-Off-By: NKirill Korotaev <dev@openvz.org>
Signed-Off-By: NLinus Torvalds <torvalds@osdl.org>