include: cleanup copyright headers

We use the code from include/ and lib/ on many places, so use public
domain if possible or LGPL for code copied from libs.

Signed-off-by: Karel Zak <kzak@redhat.com>

lib/randutils.c

@@ -1,7 +1,11 @@
 /*
  * General purpose random utilities
+ *
+ * Based on libuuid code.
+ *
+ * This file may be redistributed under the terms of the
+ * GNU Lesser General Public License.
  */
-
 #include <stdio.h>
 #include <unistd.h>
 #include <fcntl.h>