feat(ip): Complete neigh add, del, change, replace

Author: yedayak

completions/ip

@@ -379,7 +379,26 @@ _comp_cmd_ip()
         n | neigh | neighbor | neighbour)
             case $subcmd in
                 add | del | change | replace)
-                    # TODO
+                    case $prev in
+                        lladdr)
+                            _comp_compgen_mac_addresses
+                            ;;
+                        nud)
+                            _comp_cmd_ip__neigh_states "$1"
+                            ;;
+                        dev)
+                            _comp_compgen_available_interfaces
+                            ;;
+                        protocol)
+                            _comp_cmd_ip__iproute2_etc rt_protos
+                            ;;
+                        proxy)
+                            :
+                            ;;
+                        *)
+                            _comp_compgen -- -W 'lladdr nud proxy dev router use managed extern_learn protocol'
+                            ;;
+                    esac
                     ;;
                 show | flush)
                     case "$prev" in