py: Deactivate more code without MICROPY_PY_SYS

When compiler optimization has been turned on, gcc knows that this code
block is not going to be executed. But with -O0 it complains about
path_items being used uninitialized.

Signed-off-by: Sven Wegener <sven.wegener@stealer.net>

py/builtinimport.c

@@ -77,17 +77,18 @@ STATIC mp_import_stat_t stat_dir_or_file(vstr_t *path) {
 }
 
 STATIC mp_import_stat_t find_file(const char *file_str, uint file_len, vstr_t *dest) {
+#if MICROPY_PY_SYS
     // extract the list of paths
-    mp_uint_t path_num = 0;
+    mp_uint_t path_num;
     mp_obj_t *path_items;
-#if MICROPY_PY_SYS
     mp_obj_list_get(mp_sys_path, &path_num, &path_items);
-#endif
 
     if (path_num == 0) {
+#endif
         // mp_sys_path is empty, so just use the given file name
         vstr_add_strn(dest, file_str, file_len);
         return stat_dir_or_file(dest);
+#if MICROPY_PY_SYS
     } else {
         // go through each path looking for a directory or file
         for (mp_uint_t i = 0; i < path_num; i++) {
@@ -108,6 +109,7 @@ STATIC mp_import_stat_t find_file(const char *file_str, uint file_len, vstr_t *d
         // could not find a directory or file
         return MP_IMPORT_STAT_NO_EXIST;
     }
+#endif
 }
 
 STATIC void do_load(mp_obj_t module_obj, vstr_t *file) {