ip6_gre: update version related info when changing link

We forgot to update ip6erspan version related info when changing link,
which will cause setting new hwid failed.
Reported-by: NJianlin Shi <jishi@redhat.com>
Fixes: 94d7d8f2 ("ip6_gre: add erspan v2 support")
Signed-off-by: NHangbin Liu <liuhangbin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv6/ip6_gre.c

@@ -1169,6 +1169,10 @@ static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
 	t->parms.i_flags = p->i_flags;
 	t->parms.o_flags = p->o_flags;
 	t->parms.fwmark = p->fwmark;
+	t->parms.erspan_ver = p->erspan_ver;
+	t->parms.index = p->index;
+	t->parms.dir = p->dir;
+	t->parms.hwid = p->hwid;
 	dst_cache_reset(&t->dst_cache);
 }