*: 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/selinux/runcon.c b/selinux/runcon.c
index f8ca9a6..b70a5e3 100644
--- a/selinux/runcon.c
+++ b/selinux/runcon.c
@@ -26,7 +26,7 @@
  * Port to busybox: KaiGai Kohei <kaigai@kaigai.gr.jp>
  *                  - based on coreutils-5.97 (in Fedora Core 6)
  *
- * Licensed under GPLv2, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2, see file LICENSE in this source tree.
  */
 #include <getopt.h>
 #include <selinux/context.h>