drivers: code clean up

Signed-off-by: Dave Liu <daveliu@freescale.com>
diff --git a/include/sata.h b/include/sata.h
index b4b7029..57ee9ac 100644
--- a/include/sata.h
+++ b/include/sata.h
@@ -1,6 +1,11 @@
+#ifndef __SATA_H__
+#define __SATA_H__
+
 int init_sata(int dev);
 int scan_sata(int dev);
 ulong sata_read(int dev, ulong blknr, ulong blkcnt, void *buffer);
 ulong sata_write(int dev, ulong blknr, ulong blkcnt, const void *buffer);
 
 int sata_initialize(void);
+
+#endif