iwlagn: add comment to warn about WoWLAN in resume / suspend flows

WoWLAN may need the NIC even after suspend. One should not do anything to the
NIC in the bus level, since one cannot check whether WoWLAN is enabled or not.
Same for resume.

Add a simple comment to the code to warn about this.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>

drivers/net/wireless/iwlwifi/iwl-pci.c

@@ -508,6 +508,11 @@ static int iwl_pci_suspend(struct device *device)
 	struct pci_dev *pdev = to_pci_dev(device);
 	struct iwl_bus *bus = pci_get_drvdata(pdev);
 
+	/* Before you put code here, think about WoWLAN. You cannot check here
+	 * whether WoWLAN is enabled or not, and your code will run even if
+	 * WoWLAN is enabled - don't kill the NIC, someone may need it in Sx.
+	 */
+
 	return iwl_suspend(bus->drv_data);
 }
 
@@ -516,6 +521,11 @@ static int iwl_pci_resume(struct device *device)
 	struct pci_dev *pdev = to_pci_dev(device);
 	struct iwl_bus *bus = pci_get_drvdata(pdev);
 
+	/* Before you put code here, think about WoWLAN. You cannot check here
+	 * whether WoWLAN is enabled or not, and your code will run even if
+	 * WoWLAN is enabled - the NIC may be alive.
+	 */
+
 	/*
 	 * We disable the RETRY_TIMEOUT register (0x41) to keep
 	 * PCI Tx retries from interfering with C3 CPU state.