ozwpan: slight optimization of addr compare

Use possibly more efficient ether_addr_equal
instead of memcmp.

Cc: Rupesh Gujare <rupesh.gujare@atmel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: devel@driverdev.osuosl.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Tan Xiaojun <tanxiaojun@huawei.com>
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>