b43: N-PHY: clean table init, check PHY rev

Move table init to tables_nphy.c, detect newer PHY which use different init.
We don't init newer PHYs yet but this at least shows what more is needed.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>