Document that IAR gmtime_s() is auto selected
diff --git a/include/mbedtls/config.h b/include/mbedtls/config.h
index f4c8ecf..cbf8f58 100644
--- a/include/mbedtls/config.h
+++ b/include/mbedtls/config.h
@@ -149,9 +149,9 @@
* when called behaves similarly to the gmtime() function from the C standard,
* but is thread safe. Mbed TLS will try to identify the underlying platform
* and configure an appropriate underlying implementation (e.g. gmtime_r() for
- * POSIX and gmtime_s() for Windows). If this is not possible, then gmtime()
- * will be used. Refer to the documentation for mbedtls_platform_gmtime() for
- * more information.
+ * POSIX and gmtime_s() for Windows and IAR). If this is not possible, then
+ * gmtime() will be used. Refer to the documentation for
+ * mbedtls_platform_gmtime() for more information.
*
* \note It is possible to configure an implementation for
* mbedtls_platform_gmtime() at compile-time by using the macro