i40e/i40evf: Reset Head and Tail on AQ initialization

Reset head and tail on admin queue initialization where H/T are
not reset by HW.

Change-ID: I6db8a2dd3f05ce66410a92cce016191add04760e
Signed-off-by: Michal Kosiarz <michal.kosiarz@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>