Rename the _ret() functions

Signed-off-by: TRodziewicz <tomasz.rodziewicz@mobica.com>
diff --git a/programs/pkey/ecdsa.c b/programs/pkey/ecdsa.c
index 1bbf826..5a9c712 100644
--- a/programs/pkey/ecdsa.c
+++ b/programs/pkey/ecdsa.c
@@ -166,9 +166,9 @@
     mbedtls_printf( "  . Computing message hash..." );
     fflush( stdout );
 
-    if( ( ret = mbedtls_sha256_ret( message, sizeof( message ), hash, 0 ) ) != 0 )
+    if( ( ret = mbedtls_sha256( message, sizeof( message ), hash, 0 ) ) != 0 )
     {
-        mbedtls_printf( " failed\n  ! mbedtls_sha256_ret returned %d\n", ret );
+        mbedtls_printf( " failed\n  ! mbedtls_sha256 returned %d\n", ret );
         goto exit;
     }