fm10k: use napi_schedule_irqoff()

The fm10k_msix_clean_rings function runs from hard interrupt context or
with interrupts already disabled in netpoll.

It can use napi_schedule_irqoff() instead of napi_schedule()

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>