Adding pin for keepalived package

The patch sets pin priority for keepalived package version 1.2.19 to
be installed on gateway nodes as workaround for PROD-26273.

Change-Id: I59134a41f55e99804b1adcb579e683c0f223aac7
Related-PROD: PROD-26273 (PROD:26273)
diff --git a/neutron/gateway/cluster.yml b/neutron/gateway/cluster.yml
index 2a4f4f4..a159a6d 100644
--- a/neutron/gateway/cluster.yml
+++ b/neutron/gateway/cluster.yml
@@ -11,6 +11,18 @@
       kernel:
         sysctl:
           fs.inotify.max_user_instances: 4096
+# Old keepalived version has been pinned due to
+# workaround for PROD-26273 and should be removed
+# once keepalived deb package is available higher
+# 1.3.9 version
+      repo:
+        ubuntu:
+          pinning:
+            10:
+              enabled: true
+              pin: 'version 1:1.2.19-1'
+              priority: 1100
+              package: 'keepalived'
   neutron:
     gateway:
       dvr: ${_param:neutron_gateway_dvr}