lnrpc+rpcserver: add missing channel update event type

Fixes the error "unexpected channel event update" in
SubscribeChannelEvents.

lnrpc/lightning.swagger.json

@@ -3009,7 +3009,8 @@
         "ACTIVE_CHANNEL",
         "INACTIVE_CHANNEL",
         "PENDING_OPEN_CHANNEL",
-        "FULLY_RESOLVED_CHANNEL"
+        "FULLY_RESOLVED_CHANNEL",
+        "CHANNEL_FUNDING_TIMEOUT"
       ],
       "default": "OPEN_CHANNEL"
     },
@@ -4480,6 +4481,9 @@
         "fully_resolved_channel": {
           "$ref": "#/definitions/lnrpcChannelPoint"
         },
+        "channel_funding_timeout": {
+          "$ref": "#/definitions/lnrpcChannelPoint"
+        },
         "type": {
           "$ref": "#/definitions/ChannelEventUpdateUpdateType"
         }