sbi: Add definitions for true/false

We currently have TRUE/FALSE, but it could be convenient to have
true/false as well.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

include/sbi/sbi_types.h

@@ -56,6 +56,8 @@ typedef unsigned long		physical_size_t;
 
 #define TRUE			1
 #define FALSE			0
+#define true			TRUE
+#define false			FALSE
 
 #define NULL			((void *)0)