Merge pull request #1809 from Bluebear233/patch-1

Update libc.c

components/libc/compilers/newlib/libc.c

@@ -39,7 +39,7 @@ int	_EXFUN(putenv,(char *__string));
 
 int libc_system_init(void)
 {
-#if defined(RT_USING_DFS) & defined(RT_USING_DFS_DEVFS)
+#if defined(RT_USING_DFS) & defined(RT_USING_DFS_DEVFS) & defined(RT_USING_CONSOLE)
     rt_device_t dev_console;
 
     dev_console = rt_console_get_device();