[PATCH] iseries_veth: Incorporate iseries_veth.h in iseries_veth.c

iseries_veth.h is only used by iseries_veth.c, so merge the former into
the latter.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>