net: Remove redundant oif checks in rt6_device_match

The oif has already been checked that it is non-zero; the 2 additional
checks on oif within that if (oif) {...} block are redundant.

CC: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/route.c

@@ -474,10 +474,10 @@ static inline struct rt6_info *rt6_device_match(struct net *net,
 			if (dev->flags & IFF_LOOPBACK) {
 				if (!sprt->rt6i_idev ||
 				    sprt->rt6i_idev->dev->ifindex != oif) {
-					if (flags & RT6_LOOKUP_F_IFACE && oif)
+					if (flags & RT6_LOOKUP_F_IFACE)
 						continue;
-					if (local && (!oif ||
-						      local->rt6i_idev->dev->ifindex == oif))
+					if (local &&
+					    local->rt6i_idev->dev->ifindex == oif)
 						continue;
 				}
 				local = sprt;