bgpd: add memberCount into peer-grp json output

Member count is not part of current show bgp peer-group json output.

Fix:

memberCount attribute is added into bgp peer-grp json output.

Supported commands:

- show bgp peer-group json
- show bgp vrf tenant1 peer-group json

Ticket:#4073454

Testing:

tor-11# show bgp peer-group json
{
  "ISL":{
    "remoteAs":0,
    "type":"external",
    "addressFamiliesConfigured":[
      "IPv4 Unicast"
    ],
    "members":{
      "swp1":{
        "status":"Established"
      },
      "swp2":{
        "status":"Established"
      },
      "memberCount":2
    }
  }
}

Signed-off-by: Sindhu Parvathi Gopinathan's <[email protected]>

bgpd/bgp_vty.c

@@ -17083,6 +17083,7 @@ static int bgp_show_one_peer_group(struct vty *vty, struct peer_group *group,
 	json_object *json_peer_group_dynamic = NULL;
 	json_object *json_peer_group_dynamic_af = NULL;
 	json_object *json_peer_group_ranges = NULL;
+	uint16_t member_count = 0;
 
 	conf = group->conf;
 
@@ -17256,10 +17257,14 @@ static int bgp_show_one_peer_group(struct vty *vty, struct peer_group *group,
 					dynamic ? "(dynamic)" : "",
 					peer_status);
 			}
+			member_count++;
 		}
-		if (json)
+		if (json) {
+			json_object_int_add(json_peer_group_members,
+					    "memberCount", member_count);
 			json_object_object_add(json_peer_group, "members",
 					       json_peer_group_members);
+		}
 	}
 
 	if (json)