kvm: use "auto=1" in the url and backend-url

This avoids duplication of information.

software/kvm/buildout.hash.cfg

@@ -19,7 +19,7 @@ md5sum = a236b719aaac61ac342ada0ce569151a
 
 [template-kvm]
 filename = instance-kvm.cfg.jinja2
-md5sum = d604d8696815716ac51af770164e86d5
+md5sum = fd0b26e5ae200ce2f7ee2a169731998c
 
 [template-kvm-cluster]
 filename = instance-kvm-cluster.cfg.jinja2.in

software/kvm/instance-kvm.cfg.jinja2

@@ -490,8 +490,8 @@ filename = ${frontend-additional-port-execute:output}
 <= monitor-publish
 recipe = slapos.cookbook:publish
 ipv6 = ${slap-network-information:global-ipv6}
-backend-url = https://[${novnc-instance:ip}]:${novnc-instance:port}/vnc.html?host=[${novnc-instance:ip}]&port=${novnc-instance:port}&encrypt=1&password=${kvm-controller-parameter-dict:vnc-passwd}
-url = ${request-slave-frontend:connection-secure_access}/vnc.html?host=${request-slave-frontend:connection-domain}&port=${frontend-port:port}&encrypt=1&password=${kvm-controller-parameter-dict:vnc-passwd}
+backend-url = https://[${novnc-instance:ip}]:${novnc-instance:port}/vnc.html?auto=1&encrypt=1&password=${kvm-controller-parameter-dict:vnc-passwd}
+url = ${request-slave-frontend:connection-secure_access}/vnc.html?auto=1&encrypt=1&password=${kvm-controller-parameter-dict:vnc-passwd}
 {% if additional_frontend %}
 url-additional = ${request-slave-frontend-additional:connection-secure_access}/vnc.html?host=${request-slave-frontend-additional:connection-domain}&port=${frontend-additional-port:port}&encrypt=1&password=${kvm-controller-parameter-dict:vnc-passwd}
 {% endif %}