b43: LCN-PHY: implement disabling radio

b43: LCN-PHY: implement disabling radio

wl reads radio version, then disables it. That's how we found it in MMIO
dump:
 radio_read(0x0000) -> 0x0031 <-- RADIO READ WITHOUT 0x200 SET!
 radio_read(0x0001) -> 0x0064 <-- RADIO READ WITHOUT 0x200 SET!
 radio_read(0x0002) -> 0x0020 <-- RADIO READ WITHOUT 0x200 SET!
 read32 0xfaafc120 -> 0x04000400
 phy_read(0x044d) -> 0x0000
phy_write(0x044d) <- 0x0000
 phy_read(0x044c) -> 0x1fff
phy_write(0x044c) <- 0x1fff
 phy_read(0x04b7) -> 0x0000
phy_write(0x04b7) <- 0x0000
 phy_read(0x04b1) -> 0x0000
phy_write(0x04b1) <- 0x0000
 phy_read(0x04b0) -> 0x7dff
phy_write(0x04b0) <- 0x7dff
 phy_read(0x04fa) -> 0x0000
phy_write(0x04fa) <- 0x0000
 phy_read(0x04f9) -> 0x007f
phy_write(0x04f9) <- 0x007f

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