fcoe: use defines from ethtool for 20Gbit and 40Gbit speeds

Use defines from ethtool for 20Gbit and 40Gbit speeds instead of magic
numbers.
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/fcoe/fcoe_transport.c

@@ -133,10 +133,10 @@ int fcoe_link_speed_update(struct fc_lport *lport)
 		case SPEED_10000:
 			lport->link_speed = FC_PORTSPEED_10GBIT;
 			break;
-		case 20000:
+		case SPEED_20000:
 			lport->link_speed = FC_PORTSPEED_20GBIT;
 			break;
-		case 40000:
+		case SPEED_40000:
 			lport->link_speed = FC_PORTSPEED_40GBIT;
 			break;
 		default: