bgpd: Enable support for BGP IPV6 multipath.

This commit adds these two commands:
maximum-paths <1-MULTIPATH_NUM>
maximum-paths ibgp <1-MULTIPATH_NUM>

under address-family ipv6 mode.  In addition adding the ability
to pass multiple paths down into zebra from bgp.

Signed-off-by: Ayan Banerjee <ayan@cumulusnetworks.com>
Signed-off-by: Dinesh G Dutt <ddutt@cumulusnetworks.com>
Reviewed-by: Scott Feldman <sfeldma@cumulusnetworks.com>
4 files changed