Fix pointed signedness warning in yarrow-test.

ChangeLog

@@ -17,6 +17,9 @@
 	* testsuite/sexp-test.c (test_main): Use const char * for assoc
 	keys. Overlooked in 2016-08-16 change.
 
+	* testsuite/yarrow-test.c (test_main): Fix pointer
+	signednesss warning.
+
 2016-08-29  Niels Möller  <nisse@lysator.liu.se>
 
 	* sexp-format.c (strlen_u8): New helper function.

testsuite/yarrow-test.c

@@ -93,7 +93,7 @@ test_main(void)
 
   unsigned i;
   
-  static const char zeroes[100];
+  static const char unsigned zeroes[100];
 
   yarrow256_init(&yarrow, 2, sources);