add rt_console_set_device declaration.

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@463 bbd45198-f89e-11dd-88c7-29a3b14d5316

include/rtthread.h

@@ -312,7 +312,9 @@ void rt_interrupt_leave(void);
 rt_int32_t rt_sprintf(char *buf ,const char *format,...);
 rt_int32_t rt_vsprintf(char *dest, const char *format, va_list arg_ptr);
 rt_int32_t rt_sprintf(char *buf ,const char *format,...);
-rt_int32_t rt_snprintf(char *buf, rt_size_t size, const char *format, ...);
+rt_int32_t rt_snprintf(char *buf, rt_size_t size, const char *format, ...);
+
+rt_device_t rt_console_set_device(const char* name);
 void rt_kprintf(const char *fmt, ...);
 
 rt_err_t rt_get_errno(void);