It is inefficient to grab irqsave spinlocks for
skb lists for each queue/dequeue action.

Using rx_ring.lock and tx_lock allows to use less
heavy bh spinlock functions and moving locking
upwards allows to toggle spinlocks less often.
Signed-off-by: NMichal Kazior <michal.kazior@tieto.com>
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>