Second stage of qstr revamp: uPy str object can be qstr or not.
diff --git a/unix-cpy/main.c b/unix-cpy/main.c
index 0da1fca..4bd9249 100644
--- a/unix-cpy/main.c
+++ b/unix-cpy/main.c
@@ -5,6 +5,7 @@
 #include "nlr.h"
 #include "misc.h"
 #include "mpconfig.h"
+#include "qstr.h"
 #include "lexer.h"
 #include "lexerunix.h"
 #include "parse.h"