[netdrvr s/390] trim trailing whitespace

Previous fix patches added a bunch of trailing whitespace,
which git-applymbox complained loudly about.
diff --git a/drivers/s390/net/qeth_fs.h b/drivers/s390/net/qeth_fs.h
index e422b41..61faf05 100644
--- a/drivers/s390/net/qeth_fs.h
+++ b/drivers/s390/net/qeth_fs.h
@@ -42,7 +42,7 @@
 
 extern void
 qeth_remove_device_attributes_osn(struct device *dev);
-		    
+
 extern int
 qeth_create_driver_attributes(void);