[bsp] Fix STM32F10x compiling warning.

bsp/stm32f10x/drivers/board.c

@@ -19,6 +19,7 @@
 #include "stm32f10x.h"
 #include "stm32f10x_fsmc.h"
 #include "board.h"
+#include "usart.h"
 
 #ifdef  RT_USING_COMPONENTS_INIT
 #include <components.h>

bsp/stm32f10x/drivers/board.h

@@ -37,11 +37,13 @@
 #define STM32_SRAM_SIZE         64
 #define STM32_SRAM_END          (0x20000000 + STM32_SRAM_SIZE * 1024)
 
+// <<< Use Configuration Wizard in Context Menu >>>
+
 /* USART driver select. */
 #define RT_USING_UART1
 #define RT_USING_UART2
 #define RT_USING_UART3
 
-#endif /* __BOARD_H__ */
+void rt_hw_board_init(void);
 
-// <<< Use Configuration Wizard in Context Menu >>>
+#endif /* __BOARD_H__ */