i40e: use new function to clear hardware before PF reset

i40e: use new function to clear hardware before PF reset

i40e_clear_hw() was provided recently in shared code (base driver)
to clear hardware, which can cover disabling all queues.
The code changes are to remove i40e_pf_disable_all_queues() and use
i40e_clear_hw() instead.

Signed-off-by: Helin Zhang <helin.zhang@intel.com>
Acked-by: Jijiang Liu <jijiang.liu@intel.com>
Acked-by: Jing Chen <jing.d.chen@intel.com>
Tested-by: Min Cao <min.cao@intel.com>