*: 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/procps/pgrep.c b/procps/pgrep.c
index 45de8bc..5d388a8 100644
--- a/procps/pgrep.c
+++ b/procps/pgrep.c
@@ -4,7 +4,7 @@
  *
  * Copyright (C) 2007 Loic Grenie <loic.grenie@gmail.com>
  *
- * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 #include "libbb.h"
 #include "xregex.h"