CP-25328: update policy file, hubs are always denied (#3313)
CP-25328: update policy file, hubs are always denied (#3313)

Remove the DENY hubs line from policy file, because hubs are always
ignored. Also add comment to make it clear.

Signed-off-by: Xin(Talons) Li <839dcfacf023c2e3008e88a79a2cd06041865aef@citrix.com>
srowe/xen-api,srowe/xen-api,srowe/xen-api,srowe/xen-api,srowe/xen-api