*: make GNU licensing statement forms more regular

This change retains "or later" state! No licensing _changes_ here,
only form is adjusted (article, space between "GPL" and "v2" and so on).

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/networking/libiproute/utils.c b/networking/libiproute/utils.c
index 85034c0..5125617 100644
--- a/networking/libiproute/utils.c
+++ b/networking/libiproute/utils.c
@@ -2,7 +2,7 @@
 /*
  * utils.c
  *
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  *
  * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  *