libgetopts: Use iterators instead of old-style loops.

src/libgetopts/lib.rs

@@ -896,7 +896,7 @@ enum LengthLimit {
         *cont
     };
 
-    ss.char_indices().advance(|x| machine(&mut cont, x));
+    ss.char_indices().all(|x| machine(&mut cont, x));
 
     // Let the automaton 'run out' by supplying trailing whitespace
     while cont && match state { B | C => true, A => false } {