- Cleaned up warning-generating code

diff --git a/library/cipher.c b/library/cipher.c
index 545b2da..345e2fe 100644
--- a/library/cipher.c
+++ b/library/cipher.c
@@ -366,6 +366,8 @@
 
 int cipher_self_test( int verbose )
 {
+    ((void) verbose);
+
     return( 0 );
 }