Normalize NLB masters ports for dual-master

NLB in front of masters should always attach listeners over the same
ports, regardless of any configuration:

8080 for HTTP
29418 for SSH

this allows to configure the ha-proxy statically to always point to
master:8080 for http and master:29418 for SSH, for both master1 and
master2.

On the other hand however, host ports masters are exposed to can be
different and should honour configuration.

Fix ports mapping by normalizing listeners and honouring host port
configuration.

Bug: Issue 13586
Change-Id: I0a9ee0eaaac1050c3489814f404d8fd58221d681
diff --git a/dual-master/cf-service-master.yml b/dual-master/cf-service-master.yml
index 415439b..b38df4a 100644
--- a/dual-master/cf-service-master.yml
+++ b/dual-master/cf-service-master.yml
@@ -193,6 +193,7 @@
       Name: gerrit-master
     LoadBalancer:
       HTTPPort: 8080
+      SSHPort: 29418
     Container:
       HTTPPort: 8080
       SSHPort: 29418
@@ -410,7 +411,7 @@
             VpcId:
               Fn::ImportValue:
                   !Join [':', [!Ref 'ClusterStackName', 'VPCId']]
-            Port: !FindInMap ['Gerrit', 'LoadBalancer', 'HTTPPort']
+            Port: !Ref HTTPHostPort
             Protocol: TCP
 
     HTTPListener:
@@ -442,7 +443,7 @@
             - Type: forward
               TargetGroupArn: !Ref SSHTargetGroup
             LoadBalancerArn: !Ref LoadBalancer
-            Port: !Ref SSHHostPort
+            Port: !FindInMap ['Gerrit', 'LoadBalancer', 'SSHPort']
             Protocol: TCP
 
     ECSTaskExecutionRoleStack: