Fix order of #includes

This fix modifies the order of system includes to meet the ARM TF coding
standard whilst retaining header groupings.

Change-Id: Ib91968f8e2cac9e96033d73d3ad9d0a2ae228b13
Signed-off-by: Isla Mitchell <isla.mitchell@arm.com>
diff --git a/tools/fiptool/tbbr_config.c b/tools/fiptool/tbbr_config.c
index 6231cd4..7c6c24b 100644
--- a/tools/fiptool/tbbr_config.c
+++ b/tools/fiptool/tbbr_config.c
@@ -4,9 +4,10 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
-#include <firmware_image_package.h>
 #include <stddef.h>
 
+#include <firmware_image_package.h>
+
 #include "tbbr_config.h"
 
 /* The images used depends on the platform. */