e1000e: do not attempt to disable smart powerdown if not supported

During reset, the driver was attempting to disable the Smart Powerdown
feature even if the part does not support Smart Powerdown.  Check for
support before attempting to disable the feature.
Signed-off-by: NBruce Allan <bruce.w.allan@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/e1000e/netdev.c

@@ -2799,7 +2799,8 @@ void e1000e_reset(struct e1000_adapter *adapter)
 	e1000e_reset_adaptive(hw);
 	e1000_get_phy_info(hw);
 
-	if (!(adapter->flags & FLAG_SMART_POWER_DOWN)) {
+	if ((adapter->flags & FLAG_HAS_SMART_POWER_DOWN) &&
+	    !(adapter->flags & FLAG_SMART_POWER_DOWN)) {
 		u16 phy_data = 0;
 		/*
 		 * speed up time to link by disabling smart power down, ignore