MAAS: set kernel to virtual-hwe-16.04

  * Misc: drop odd port definion

Change-Id: I8839da2175d0d4f3d1391a2becf91e944737a98f
Related-Bug: PROD-25084 (PROD:25084)
(cherry picked from commit c48c3879c48b8bff25a25fc1b8d8609a5f29411e)
diff --git a/maas/region/single.yml b/maas/region/single.yml
index 3569fff..9d60882 100644
--- a/maas/region/single.yml
+++ b/maas/region/single.yml
@@ -10,8 +10,12 @@
       enabled: true
       role: master
       region:
-        host: ${_param:single_address}
-        port: 5242
+        host: ${_param:single_address}:5242
+      curtin_vars:
+        amd64:
+          xenial:
+            extra_pkgs: [ "linux-headers-virtual-hwe-16.04", "linux-image-extra-virtual-hwe-16.04" ]
+            kernel_package: 'linux-image-virtual-hwe-16.04'
     region:
       salt_master_ip: ${_param:infra_config_deploy_address}
       theme: mirantis