[Patch] xtensa: fix a build error in arch/xtensa/include/asm/uaccess.h

[AmÃrico Wang]

This patch fixes the following build error,


src/arch/xtensa/include/asm/uaccess.h:403: error: implicit declaration
of function 'prefetch': 1 errors in 1 logs
        v3.0-rc6/xtensa/xtensa-defconfig
src/arch/xtensa/include/asm/uaccess.h:412: error: implicit declaration
of function 'prefetchw': 1 errors in 1 logs
        v3.0-rc6/xtensa/xtensa-defconfig

Signed-off-by: WANG Cong <xiyou.wangcong@xxxxxxxxx>
Cc: Chris Zankel <chris@xxxxxxxxxx>

---
diff --git a/arch/xtensa/include/asm/uaccess.h b/arch/xtensa/include/asm/uaccess.h
index 5b0c18c..c141b11 100644
--- a/arch/xtensa/include/asm/uaccess.h
+++ b/arch/xtensa/include/asm/uaccess.h
@@ -17,6 +17,7 @@
 #define _XTENSA_UACCESS_H
 
 #include <linux/errno.h>
+#include <linux/prefetch.h>
 
 #define VERIFY_READ    0
 #define VERIFY_WRITE   1