added const qualifier

diff --git a/skeletons/NativeReal.c b/skeletons/NativeReal.c
index 810d510..5bc95b0 100644
--- a/skeletons/NativeReal.c
+++ b/skeletons/NativeReal.c
@@ -45,7 +45,7 @@
 asn_dec_rval_t
 NativeReal_decode_ber(asn_codec_ctx_t *opt_codec_ctx,
 	asn_TYPE_descriptor_t *td,
-	void **dbl_ptr, void *buf_ptr, size_t size, int tag_mode) {
+	void **dbl_ptr, const void *buf_ptr, size_t size, int tag_mode) {
 	double *Dbl = (double *)*dbl_ptr;
 	asn_dec_rval_t rval;
 	ber_tlv_len_t length;
@@ -79,7 +79,7 @@
 	/*
 	 * Make sure we have this length.
 	 */
-	buf_ptr = ((char *)buf_ptr) + rval.consumed;
+	buf_ptr = ((const char *)buf_ptr) + rval.consumed;
 	size -= rval.consumed;
 	if(length > (ber_tlv_len_t)size) {
 		rval.code = RC_WMORE;
@@ -95,7 +95,7 @@
 	{
 		REAL_t tmp;
 		double d;
-		tmp.buf = (uint8_t *)buf_ptr;
+		(const uint8_t *)tmp.buf = (const uint8_t *)buf_ptr;
 		tmp.size = length;
 
 		if(asn_REAL2double(&tmp, &d)) {
@@ -158,7 +158,7 @@
 asn_dec_rval_t
 NativeReal_decode_xer(asn_codec_ctx_t *opt_codec_ctx,
 	asn_TYPE_descriptor_t *td, void **sptr, const char *opt_mname,
-		void *buf_ptr, size_t size) {
+		const void *buf_ptr, size_t size) {
 	asn_dec_rval_t rval;
 	REAL_t *st = 0;
 	double *Dbl = (double *)*sptr;