Crypto: Align to PSA Crypto headers 0.1.0a

This patch updates the PSA Crypto API headers to version
0.1.0a. The Crypto service implementation is updated when
needed to make sure the service is buildable and functional.

Change-Id: I63709db0d87f449012d0c8355658f1af1583b3ab
Signed-off-by: Antonio de Angelis <antonio.deangelis@arm.com>
diff --git a/interface/include/psa_crypto_extra.h b/interface/include/psa_crypto_extra.h
index d8fabf7..1608410 100644
--- a/interface/include/psa_crypto_extra.h
+++ b/interface/include/psa_crypto_extra.h
@@ -1,40 +1,35 @@
 /*
- * Copyright (c) 2018, Arm Limited. All rights reserved.
+ * Copyright (c) 2018-2019, Arm Limited. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  *
  */
-
 /**
  * \file psa_crypto_extra.h
  *
  * \brief PSA cryptography module: vendor extensions
+ *
+ * \note This file may not be included directly. Applications must
+ * include psa_crypto.h.
+ *
+ * This file is reserved for vendor-specific definitions.
  */
 
-#ifndef __PSA_CRYPTO_EXTRA_H__
-#define __PSA_CRYPTO_EXTRA_H__
+/**
+ *\note This implementation currently doesn't provide support to any
+ *      vendor-specific extension or definition, so this header file
+ *      is empty.
+ */
+
+#ifndef PSA_CRYPTO_EXTRA_H
+#define PSA_CRYPTO_EXTRA_H
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-/**
- * \note This file is meant to be included by psa_crypto.h only
- *
- */
-
-/**
- * \brief Library deinitialization.
- *
- * This function clears all data associated with the PSA layer,
- * including the whole key store.
- *
- * This is an Mbed TLS extension.
- */
-void mbedtls_psa_crypto_free(void);
-
 #ifdef __cplusplus
 }
 #endif
 
-#endif /* __PSA_CRYPTO_EXTRA_H__ */
+#endif /* PSA_CRYPTO_EXTRA_H */