ar9170: Use const

Mark an array const.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ar9170/cmd.c b/drivers/net/wireless/ath/ar9170/cmd.c
index 4604de0..6452c50 100644
--- a/drivers/net/wireless/ath/ar9170/cmd.c
+++ b/drivers/net/wireless/ath/ar9170/cmd.c
@@ -54,7 +54,7 @@
 
 int ar9170_write_reg(struct ar9170 *ar, const u32 reg, const u32 val)
 {
-	__le32 buf[2] = {
+	const __le32 buf[2] = {
 		cpu_to_le32(reg),
 		cpu_to_le32(val),
 	};