b43: N-PHY: fixes for radio 0x2057

Enable initialization and update calibration code to fix:
b43-phy0 ERROR: Radio 0x2057 rcal timeout
b43-phy0 debug: Radio 0x2057 rccal timeout
b43-phy0 debug: Radio 0x2057 rccal timeout
b43-phy0 ERROR: Radio 0x2057 rcal timeout

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