e1000e: Minor flow correction in e1000_shutdown function

Add curly braces to avoid entering to an if statement where it is not
always required in e1000_shutdown function.
This improves code readability and might prevent non-deterministic
behaviour in the future.

Signed-off-by: Vitaly Lifshits <vitaly.lifshits@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Link: https://lore.kernel.org/r/20240301184806.2634508-5-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/intel/e1000e/netdev.c

@@ -6688,14 +6688,14 @@ static int __e1000_shutdown(struct pci_dev *pdev, bool runtime)
 	if (adapter->hw.phy.type == e1000_phy_igp_3) {
 		e1000e_igp3_phy_powerdown_workaround_ich8lan(&adapter->hw);
 	} else if (hw->mac.type >= e1000_pch_lpt) {
-		if (wufc && !(wufc & (E1000_WUFC_EX | E1000_WUFC_MC | E1000_WUFC_BC)))
+		if (wufc && !(wufc & (E1000_WUFC_EX | E1000_WUFC_MC | E1000_WUFC_BC))) {
 			/* ULP does not support wake from unicast, multicast
 			 * or broadcast.
 			 */
 			retval = e1000_enable_ulp_lpt_lp(hw, !runtime);
-
-		if (retval)
-			return retval;
+			if (retval)
+				return retval;
+		}
 	}
 
 	/* Ensure that the appropriate bits are set in LPI_CTRL