iwlwifi: stop interrupts before stopping device

If an RX interrupt is signalled after or during apm_stop
we may try to access the peripherals which are already
down. Prevent this by disabling interrupts first.

Signed-off-by: David Spinadel <david.spinadel@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/iwlwifi/pcie/trans.c

@@ -1453,6 +1453,10 @@ static void iwl_trans_pcie_stop_hw(struct iwl_trans *trans,
 	bool hw_rfkill;
 	unsigned long flags;
 
+	spin_lock_irqsave(&trans_pcie->irq_lock, flags);
+	iwl_disable_interrupts(trans);
+	spin_unlock_irqrestore(&trans_pcie->irq_lock, flags);
+
 	iwl_apm_stop(trans);
 
 	spin_lock_irqsave(&trans_pcie->irq_lock, flags);