isaac, crcsync: acknowledge licensing issues.

The recently added ccanlint licensing checks revealed several cases
where the published license of a module is misleading: a dependency of
that module has a stricter license (eg. a public domain module which
depends on a GPL one).

Where these are my modules, I've fixed them.  Otherwise I'm overriding
the checks for the moment, and asking the authors what they want to do.

ccan/crcsync/_info

@@ -69,6 +69,9 @@
  *
  * License: LGPL (v2.1 or any later version)
  * Author: Rusty Russell <rusty@rustcorp.com.au>
+ * Ccanlint:
+ *	// We actually depend on the GPL crc routines, so not really LGPL :(
+ *	license_depends_compat FAIL
  */
 int main(int argc, char *argv[])
 {

ccan/isaac/_info

@@ -100,6 +100,9 @@
  *  }
  *
  * License: Public Domain
+ * Ccanlint:
+ *	// We actually depend on the LGPL ilog routines, so not PD :(
+ *	license_depends_compat FAIL
  */
 #include <string.h>
 #include <stdio.h>