[kernel] Fix handle_list count bug

The handle_list syscall was returning j6_err_insufficient with inverted
logic - when the provided array was NOT too small.

src/kernel/syscalls/handle.cpp

@@ -16,7 +16,7 @@ handle_list(j6_handle_t *handles, size_t *handles_len)
 
     *handles_len = p.list_handles(handles, requested);
 
-    if (*handles_len < requested)
+    if (*handles_len > requested)
         return j6_err_insufficient;
 
     return j6_status_ok;