skip generating etherenet_mac_address when null

* Host-generator template is generating a null value like below when host
  catalogue is not having any mac value for the interface.
  ethernet_mac_address: <no value>

* added another condition to ethernet_mac_address generation logic
  so generate only if macAddresses is provided and if it has
  value for the respective interface ( oam, pxe ...)

Closes: #404
Change-Id: I2fafe5ceaa4c58855a17929c1c41d60045d1675a

krm-functions/templater/local-resource/example-use.yaml

@@ -18,10 +18,16 @@ metadata:
         image: localhost/templater
 values:
   hosts:
-  - macAddress: 00:aa:bb:cc:dd
+  - macAddresses:
+      oam: 00:aa:bb:cc:dd
+      pxe: 00:aa:bb:cc:ee
     name: node-1
-  - macAddress: 00:aa:bb:cc:ee
+  - macAddresses:
+      oam: 00:aa:bb:cc:ff
     name: node-2
+  - macAddresses:
+      pxe: 00:aa:bb:cc:22
+    name: node-3
 template: |
   {{ range .hosts -}}
   ---
@@ -30,5 +36,7 @@ template: |
   metadata:
     name: {{ .name }}
   spec:
-    bootMACAddress: {{ .macAddress }}
+    {{- if and (.macAddresses) (.macAddresses.oam) }}
+    bootMACAddress: {{ .macAddresses.oam }}
+    {{- end }}
   {{ end -}}

manifests/function/hostgenerator-m3/hosttemplate.yaml

@@ -92,7 +92,7 @@ template: |
         {{- range $envAll.commonNetworking.links }}
       -
   {{ toYaml . | indent 6 }}
-        {{- if $host.macAddresses }}
+        {{- if and ($host.macAddresses) (index $host.macAddresses .id) }}
         ethernet_mac_address: {{ index $host.macAddresses .id }}
         {{- end }}
         {{- end }}