Allow BGP port override (#1493)

Co-authored-by: Devin Buhl <onedr0p@users.noreply.github.com>

bootstrap/templates/kubernetes/apps/kube-system/cilium/config/cilium-l3.yaml.j2

@@ -16,6 +16,9 @@ spec:
         #% for item in bootstrap_bgp.peers %#
         - peerAddress: "#{ item }#/32"
           peerASN: #{ bootstrap_bgp.peer_asn }#
+        #% if bootstrap_bgp.peer_port %#
+          peerPort: #{ bootstrap_bgp.peer_port }#
+        #% endif %#
         #% endfor %#
         #% else %#
         #% if bootstrap_node_default_gateway %#

config.sample.yaml

@@ -85,6 +85,9 @@ bootstrap_bgp:
   #   If these match, iBGP will be used. If not, eBGP will be used.
   peer_asn: ""  # Router(s) AS
   local_asn: "" # Node(s) AS
+  # (Optional) If using a non-default BGP port.
+  #   Default is 179 (tcp).
+  # peer_port: "" # BGP Port
   # (Required) The advertised CIDR for the cluster, this must NOT overlap with any
   #   existing networks and is usually a /16 (64K IPs).
   # If you want to use IPv6 check the advanced flags below