fix: keep oxia istio config scoped

Author: mattisonchao

charts/sn-platform/templates/oxia/oxia-cluster.yaml

@@ -23,9 +23,6 @@ spec:
   {{- if .Values.istio.enabled }}
   istio:
     enabled: true
-    {{- if .Values.istio.dataplaneMode }}
-    dataplaneMode: {{ .Values.istio.dataplaneMode }}
-    {{- end }}
     {{- if .Values.istio.migration }}
     mtls:
       mode: permissive

charts/sn-platform/values.yaml

@@ -2930,11 +2930,6 @@ istio:
   # mergeMetrics should be enabled if you want to scrape pulsar metrics from an external prometheus not running on Istio
   # prometheus and grafana will not be Istio injected if mergeMetrics is enabled
   mergeMetrics: false
-  # Istio data plane mode: "sidecar" or "ambient"
-  # - sidecar: Traditional per-pod sidecars (default if empty)
-  # - ambient: Sidecar-less data plane using ztunnel for L4 mTLS
-  # Leave empty for default behavior (sidecar mode)
-  dataplaneMode: ""
   gateway:
     # gateway selector if it's not `istio: ingressgateway`
     selector: {}