Bugfix in sieve library

* libmu_sieve/sieve-gram.y: Add missing assignment to $$ in testlist
production.  This fixes improper handling of anyof and allof

@@ -180,6 +180,7 @@ testlist     : cond
 		 $3->prev = $1.tail;
 		 $1.tail->next = $3;
 		 $1.tail = $3;
+		 $$ = $1;
 	       }
              ;