Eliminate another warning.

arch/arm/src/tiva/tiva_start.h

@@ -43,20 +43,21 @@
 #include <nuttx/config.h>
 
 /****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/****************************************************************************
- * Public Types
+ * Public Functions
  ****************************************************************************/
 
 /****************************************************************************
- * Public Data
+ * Name: tiva_boardinitialize
+ *
+ * Description:
+ *   All Tiva architectures must provide the following entry point.  This
+ *   entry point is called early in the initialization -- after clocking and
+ *   memory have been configured but before caches have been enabled and
+ *   before any devices have been initialized.
+ *
  ****************************************************************************/
 
-/****************************************************************************
- * Public Functions
- ****************************************************************************/
+void tiva_boardinitialize(void);
 
 /****************************************************************************
  * Name: board_earlyinit