Add support for securityContext

This commit adds an optional value to template out securityContext for
the deployment.

Signed-off-by: Devon Mizelle <[email protected]>

Author: Devon Mizelle

stable/coredns/templates/deployment.yaml

@@ -127,6 +127,10 @@ spec:
             exec:
               command: ["/usr/bin/sleep", "{{ .Values.preStopSleep }}"]
         {{- end }}
+{{- if .Values.securityContext }}
+        securityContext:
+{{- toYaml .Values.securityContext | nindent 10 }}
+{{- end }}
       volumes:
         - name: config-volume
           configMap: