Expose mbedtls_error_to_psa_status for use in test drivers

Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
diff --git a/include/psa/crypto_extra.h b/include/psa/crypto_extra.h
index f0c7979..2ac2c5b 100644
--- a/include/psa/crypto_extra.h
+++ b/include/psa/crypto_extra.h
@@ -645,6 +645,17 @@
                                                size_t byte_length );
 #endif /* MBEDTLS_ECP_C */
 
+/** Convert an mbed TLS error code to a PSA error code
+ *
+ * \note This function is provided solely for the convenience of
+ *       Mbed TLS and may be removed at any time without notice.
+ *
+ * \param ret           An mbed TLS-thrown error code
+ *
+ * \return              The corresponding PSA error code
+ */
+psa_status_t mbedtls_to_psa_error( int ret );
+
 /**@}*/
 
 #ifdef __cplusplus
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index edef287..7da2ff6 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -125,7 +125,7 @@
     if( global_data.initialized == 0 )  \
         return( PSA_ERROR_BAD_STATE );
 
-static psa_status_t mbedtls_to_psa_error( int ret )
+psa_status_t mbedtls_to_psa_error( int ret )
 {
     /* If there's both a high-level code and low-level code, dispatch on
      * the high-level code. */