[bsp] Fix missing header file applications in ls2k

Author: junchao-loongson

bsp/ls2kdev/drivers/drv_spi.c

@@ -14,6 +14,7 @@
 /*@{*/
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdint.h>
 #include <ctype.h>
 #include <rtthread.h>
 #include <drivers/spi.h>