mwifiex: replace kmalloc & memcpy sequence with kmemdup

Sequence of kmalloc/kzalloc and memcpy is replaced with
kmemdup.

Cc: Walter Harms <wharms@bfs.de>
Signed-off-by: Yogesh Ashok Powar <yogeshp@marvell.com>
Signed-off-by: Kiran Divekar <dkiran@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/mwifiex/join.c b/drivers/net/wireless/mwifiex/join.c
index 5cdad92..62b4c29 100644
--- a/drivers/net/wireless/mwifiex/join.c
+++ b/drivers/net/wireless/mwifiex/join.c
@@ -147,13 +147,12 @@
 	u8 *ptr = rate1, *tmp;
 	u32 i, j;
 
-	tmp = kmalloc(rate1_size, GFP_KERNEL);
+	tmp = kmemdup(rate1, rate1_size, GFP_KERNEL);
 	if (!tmp) {
 		dev_err(priv->adapter->dev, "failed to alloc tmp buf\n");
 		return -ENOMEM;
 	}
 
-	memcpy(tmp, rate1, rate1_size);
 	memset(rate1, 0, rate1_size);
 
 	for (i = 0; rate2[i] && i < rate2_size; i++) {