adding ability to use an existing Secret for s3

k8s/charts/seaweedfs/templates/s3-deployment.yaml

@@ -121,9 +121,11 @@ spec:
             - name: logs
               mountPath: "/logs/"
             {{- end }}
+            {{- if .Values.s3.enableAuth }}
             - mountPath: /etc/sw
               name: config-users
               readOnly: true
+            {{- end }}
             {{- if .Values.global.enableSecurity }}
             - name: security-config
               readOnly: true
@@ -182,10 +184,16 @@ spec:
             {{ tpl .Values.s3.resources . | nindent 12 | trim }}
           {{- end }}
       volumes:
+        {{- if .Values.s3.enableAuth }}
         - name: config-users
           secret:
             defaultMode: 420
+            {{- if .Values.filer.s3.existingConfigSecret }}
+            secretName: {{ .Values.s3.existingConfigSecret }}
+            {{- else }}
             secretName: seaweedfs-s3-secret
+            {{- end }}
+        {{- end }}
         {{- if eq .Values.s3.logs.type "hostPath" }}
         - name: logs
           hostPath: