psa: Export "internally" mbedtls_cipher_info_from_psa

Export "internally" mbedtls_cipher_info_from_psa to be
able to use it in psa_crypto_cipher.c.

Signed-off-by: Ronald Cron <ronald.cron@arm.com>
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index 3c8b97d..94d0c05 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -2310,7 +2310,7 @@
 /* MAC */
 /****************************************************************/
 
-static const mbedtls_cipher_info_t *mbedtls_cipher_info_from_psa(
+const mbedtls_cipher_info_t *mbedtls_cipher_info_from_psa(
     psa_algorithm_t alg,
     psa_key_type_t key_type,
     size_t key_bits,
diff --git a/library/psa_crypto_core.h b/library/psa_crypto_core.h
index ec7ac80..f949c71 100644
--- a/library/psa_crypto_core.h
+++ b/library/psa_crypto_core.h
@@ -212,6 +212,22 @@
  */
 psa_status_t mbedtls_to_psa_error( int ret );
 
+/** Get Mbed TLS cipher information given the cipher algorithm PSA identifier
+ *  as well as the PSA type and size of the key to be used with the cipher
+ *  algorithm.
+ *
+ * \param       alg        PSA cipher algorithm identifier
+ * \param       key_type   PSA key type
+ * \param       key_bits   Size of the key in bits
+ * \param[out]  cipher_id  Mbed TLS cipher algorithm identifier
+ *
+ * \return  The Mbed TLS cipher information of the cipher algorithm.
+ *          \c NULL if the PSA cipher algorithm is not supported.
+ */
+const mbedtls_cipher_info_t *mbedtls_cipher_info_from_psa(
+    psa_algorithm_t alg, psa_key_type_t key_type, size_t key_bits,
+    mbedtls_cipher_id_t *cipher_id );
+
 /** Import a key in binary format.
  *
  * \note The signature of this function is that of a PSA driver