MLECO-2983: Preliminary support to allow semihosting

Adding basic support to allow applications to build with semihosting
support. Default state is always disabled.

Signed-off-by: Kshitij Sisodia <kshitij.sisodia@arm.com>
Change-Id: I1d34c3a246560aaffcb34eee801e1a87d887d559
diff --git a/source/hal/platform/mps3/source/platform_drivers.c b/source/hal/platform/mps3/source/platform_drivers.c
index 3046c12..fc119ab 100644
--- a/source/hal/platform/mps3/source/platform_drivers.c
+++ b/source/hal/platform/mps3/source/platform_drivers.c
@@ -17,9 +17,9 @@
 
 #include "platform_drivers.h"
 
-#include "uart_stdout.h"    /* stdout over UART. */
 #include "log_macros.h"     /* Logging functions */
 #include "device_mps3.h"    /* FPGA level definitions and functions. */
+#include "uart_stdout.h"    /* stdout over UART. */
 
 #include <string.h>         /* For strncpy */