SDFAB-993 Optimize helm values across component and umbrella chart

Also fix an NPE in secret-registry.yaml

Change-Id: I8178cfa050226482c0027b5a093bf4ef61a2b790
diff --git a/pfcp-agent/values.yaml b/pfcp-agent/values.yaml
index 08a48e1..ec37c12 100644
--- a/pfcp-agent/values.yaml
+++ b/pfcp-agent/values.yaml
@@ -7,9 +7,6 @@
     init: registry.aetherproject.org/tools/busybox:stable
     pfcpiface: "registry.aetherproject.org/proxy/omecproject/upf-epc-pfcpiface:master-fcdbc95"
   pullPolicy: Always
-  # Secrets must be manually created in the namespace.
-  pullSecrets:
-    - "aether.registry"
 
 nodeSelectors:
   enabled: false
@@ -37,9 +34,12 @@
         measure: true
         enable_p4rt: true
         p4rtciface:
+          # Should be the same as s1uAddr in ONOS netcfg for the UP4 app.
           access_ip: "172.17.0.1/32"
+          # Do not change unless you are deploying ONOS in a custom way.
           p4rtc_server: "sdfabric-onos-classic-hs"
           p4rtc_port: "51001"
+
 service:
   type: ClusterIP
   #externalIp: