constness fixes, round-trip and fuzz-testing for CHOICE
diff --git a/skeletons/NativeEnumerated_oer.c b/skeletons/NativeEnumerated_oer.c
index 9b0c0d3..3222348 100644
--- a/skeletons/NativeEnumerated_oer.c
+++ b/skeletons/NativeEnumerated_oer.c
@@ -31,7 +31,7 @@
 
 asn_dec_rval_t
 NativeEnumerated_decode_oer(const asn_codec_ctx_t *opt_codec_ctx,
-                            asn_TYPE_descriptor_t *td,
+                            const asn_TYPE_descriptor_t *td,
                             const asn_oer_constraints_t *constraints,
                             void **nint_ptr, const void *ptr, size_t size) {
     asn_dec_rval_t rval = {RC_OK, 0};
@@ -99,9 +99,9 @@
  * Encode as Canonical OER.
  */
 asn_enc_rval_t
-NativeEnumerated_encode_oer(asn_TYPE_descriptor_t *td,
+NativeEnumerated_encode_oer(const asn_TYPE_descriptor_t *td,
                             const asn_oer_constraints_t *constraints,
-                            void *sptr, asn_app_consume_bytes_f *cb,
+                            const void *sptr, asn_app_consume_bytes_f *cb,
                             void *app_key) {
     asn_enc_rval_t er;
     long native;