Reduce the number of bootenv vars

docs/ota.md

@@ -1,10 +1,12 @@
 ## Upgrade process
 
-We use a CRD with an agent to handle this. Our versions follows upstream's.
+We use an agent to watch the OSUpgrade CRD to handle this. Our image versions follows upstream.
 
 To issue an upgrade. Simply use
 
 kubectl apply -f upgrade.yaml
+
+Example yaml
 ```yaml
 apiVersion: monok8s.io/v1alpha1
 kind: OSUpgrade
@@ -12,8 +14,6 @@ metadata:
   name: "my-ugrade-2"
 spec:
   version: "v1.35.3"
-  imageURL: "https://updates.example.com/monok8s-1.2.3.img.zst"
-  checksum: "sha256:..."
   nodeSelector: {}
   catalog:
     inline: |
@@ -39,7 +39,7 @@ spec:
         - v1.34.0
 ```
 
-catalog accepts URL or ConfigMap
+catalog also accepts URL or ※ConfigMap
 ```yaml
 catalog:
   URL: https://example.com/images.yaml
@@ -48,6 +48,9 @@ catalog:
   ConfigMap: images-cm
 ```
 
+※ ConfigMap requires additional RBAC permission which is not by default. You edit the
+control-agent ClusterRole and add `cnofigmaps: get` to allow this.
+
 Contents should look like this
 ```yaml
 stable: v1.35.1