i40e: Fix a sleep-in-atomic bug

The driver may sleep under a spin lock, and the function call path is:
i40e_ndo_set_vf_port_vlan (acquire the lock by spin_lock_bh)
  i40e_vsi_remove_pvid
    i40e_vlan_stripping_disable
      i40e_aq_update_vsi_params
        i40e_asq_send_command
          mutex_lock --> may sleep

To fixed it, the spin lock is released before "i40e_vsi_remove_pvid", and
the lock is acquired again after this function.

Signed-off-by: Jia-Ju Bai <baijiaju1990@163.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>