net: vrf: Add support for PREROUTING rules on vrf device
Add support for PREROUTING rules with skb->dev set to the vrf device. INPUT rules are already allowed. Provides symmetry with the output path which allows POSTROUTING rules. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>