staging: rtl8188eu: Use is_{zero/broadcast}_ether_addr() instead of memcmp()

Simplify the code by using is_{zero/broadcast}_ether_addr() instead of
directly using memcmp() to determine if the ethernet address is all
zeros or broadcast address.

Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Link: https://lore.kernel.org/r/20210609085650.1269008-1-liushixin2@huawei.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>