pcmcia: use kstrdup() in pcmcia_device_query()

Use kstrdup instead of kmalloc and strncpy.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/pcmcia/ds.c b/drivers/pcmcia/ds.c
index 0decee6..489ea10 100644
--- a/drivers/pcmcia/ds.c
+++ b/drivers/pcmcia/ds.c
@@ -468,12 +468,10 @@
 			if ((length < 2) || (length > 255))
 				continue;
 
-			new = kmalloc(sizeof(char) * length, GFP_KERNEL);
+			new = kstrdup(tmp, GFP_KERNEL);
 			if (!new)
 				continue;
 
-			new = strncpy(new, tmp, length);
-
 			tmp = p_dev->prod_id[i];
 			p_dev->prod_id[i] = new;
 			kfree(tmp);