py: Change qstr_* functions to use size_t as the type for str len arg.
diff --git a/py/qstr.h b/py/qstr.h
index 04ef4c3..333c60f 100644
--- a/py/qstr.h
+++ b/py/qstr.h
@@ -57,19 +57,19 @@
 
 void qstr_init(void);
 
-mp_uint_t qstr_compute_hash(const byte *data, mp_uint_t len);
-qstr qstr_find_strn(const char *str, mp_uint_t str_len); // returns MP_QSTR_NULL if not found
+mp_uint_t qstr_compute_hash(const byte *data, size_t len);
+qstr qstr_find_strn(const char *str, size_t str_len); // returns MP_QSTR_NULL if not found
 
 qstr qstr_from_str(const char *str);
-qstr qstr_from_strn(const char *str, mp_uint_t len);
+qstr qstr_from_strn(const char *str, size_t len);
 
-byte *qstr_build_start(mp_uint_t len, byte **q_ptr);
+byte *qstr_build_start(size_t len, byte **q_ptr);
 qstr qstr_build_end(byte *q_ptr);
 
 mp_uint_t qstr_hash(qstr q);
 const char *qstr_str(qstr q);
-mp_uint_t qstr_len(qstr q);
-const byte *qstr_data(qstr q, mp_uint_t *len);
+size_t qstr_len(qstr q);
+const byte *qstr_data(qstr q, size_t *len);
 
 void qstr_pool_info(mp_uint_t *n_pool, mp_uint_t *n_qstr, mp_uint_t *n_str_data_bytes, mp_uint_t *n_total_bytes);
 void qstr_dump_data(void);