e1000e: Warn if disabling ULP failed

The hardware may stop working if driver failed to disable ULP mode.

Take the return value of e1000_disable_ulp_lpt_lp() into account, and
pass up the error if it fails.

Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/e1000e/ich8lan.c

@@ -300,7 +300,11 @@ static s32 e1000_init_phy_workarounds_pchlan(struct e1000_hw *hw)
 	 * so forcibly disable it.
 	 */
 	hw->dev_spec.ich8lan.ulp_state = e1000_ulp_state_unknown;
-	e1000_disable_ulp_lpt_lp(hw, true);
+	ret_val = e1000_disable_ulp_lpt_lp(hw, true);
+	if (ret_val) {
+		e_warn("Failed to disable ULP\n");
+		goto out;
+	}
 
 	ret_val = hw->phy.ops.acquire(hw);
 	if (ret_val) {