udp: Handle VRF device in sendmsg
udp: Handle VRF device in sendmsg

For unconnected UDP sockets using a VRF device lookup source address
based on VRF table. This allows the UDP header to be properly setup
before showing up at the VRF device via the dst.

Signed-off-by: Shrijeet Mukherjee <62b2e2e3d24633e33bb2cfda21ff188924e9f61e@cumulusnetworks.com>
Signed-off-by: David Ahern <e908389d4bbf30e8dc72dc47cdf6b45d89e8b2a0@cumulusnetworks.com>
Signed-off-by: David S. Miller <fe08d3c717adf2ae63592e4c9aec6e3e404d8e3e@davemloft.net>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs