driver: tty: serial: remove cast for kzalloc return value

remove cast for kzalloc return value.
Signed-off-by: NZhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-serial@vger.kernel.org
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

drivers/tty/serial/icom.c

@@ -1415,8 +1415,7 @@ static int icom_alloc_adapter(struct icom_adapter
 	struct icom_adapter *cur_adapter_entry;
 	struct list_head *tmp;
 
-	icom_adapter = (struct icom_adapter *)
-	    kzalloc(sizeof(struct icom_adapter), GFP_KERNEL);
+	icom_adapter = kzalloc(sizeof(struct icom_adapter), GFP_KERNEL);
 
 	if (!icom_adapter) {
 		return -ENOMEM;