int rc is unmodified after initalization in net/ipv4/route.c, this patch simply cleans up that variable and returns 0.

This was found with coccicheck M=net/ipv4/ on linus' tree.
Signed-off-by: NTim Hansen <devtimhansen@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>