parser schema CHANGE always return non-const modules

Refs #1645
diff --git a/tools/re/main.c b/tools/re/main.c
index 4d8aa99..9ef32eb 100644
--- a/tools/re/main.c
+++ b/tools/re/main.c
@@ -124,7 +124,7 @@
     int *invert_match = NULL;
     int patterns_count = 0;
     struct ly_ctx *ctx = NULL;
-    const struct lys_module *mod;
+    struct lys_module *mod;
     FILE *infile = NULL;
     size_t len = 0;
     ssize_t l;