Deprecate mbedtls_asn1_free_named_data()

Signed-off-by: Glenn Strauss <gstrauss@gluelogic.com>
diff --git a/include/mbedtls/asn1.h b/include/mbedtls/asn1.h
index 5d27495..8b66ee2 100644
--- a/include/mbedtls/asn1.h
+++ b/include/mbedtls/asn1.h
@@ -24,6 +24,7 @@
 #include "mbedtls/private_access.h"
 
 #include "mbedtls/build_info.h"
+#include "mbedtls/platform_util.h"
 
 #include <stddef.h>
 
@@ -606,22 +607,29 @@
 const mbedtls_asn1_named_data *mbedtls_asn1_find_named_data( const mbedtls_asn1_named_data *list,
                                        const char *oid, size_t len );
 
+#if !defined(MBEDTLS_DEPRECATED_REMOVED)
 /**
  * \brief       Free a mbedtls_asn1_named_data entry
  *
+ * \deprecated  This function is deprecated and will be removed in a
+ *              future version of the library.
+ *              Please use mbedtls_asn1_free_named_data_list()
+ *              or mbedtls_asn1_free_named_data_list_shallow().
+ *
  * \param entry The named data entry to free.
  *              This function calls mbedtls_free() on
  *              `entry->oid.p` and `entry->val.p`.
  */
-void mbedtls_asn1_free_named_data( mbedtls_asn1_named_data *entry );
+void MBEDTLS_DEPRECATED mbedtls_asn1_free_named_data( mbedtls_asn1_named_data *entry );
+#endif /* MBEDTLS_DEPRECATED_REMOVED */
 
 /**
  * \brief       Free all entries in a mbedtls_asn1_named_data list.
  *
  * \param head  Pointer to the head of the list of named data entries to free.
- *              This function calls mbedtls_asn1_free_named_data() and
- *              mbedtls_free() on each list element and
- *              sets \c *head to \c NULL.
+ *              This function calls mbedtls_free() on
+ *              `entry->oid.p` and `entry->val.p` and then on `entry`
+ *              for each list entry, and sets \c *head to \c NULL.
  */
 void mbedtls_asn1_free_named_data_list( mbedtls_asn1_named_data **head );