net: w5100: fix MAC filtering for W5500

W5500 has different bit position for MAC filter in Socket n mode
register from W5100 and W5200.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Mike Sinkovsky <msink@permonline.ru>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>