Merge pull request #10427 from sworleys/Protodown-Reason-Upstream

Add Support for Setting Protodown Reason Code

diff --cc sharpd/sharp_zebra.c
Simple merge

diff --cc zebra/dplane_fpm_nl.c
Simple merge

diff --cc zebra/if_netlink.c
Simple merge

diff --cc zebra/zebra_vty.c
Simple merge