b43: LP-PHY: Update baseband init for recent spec changes

The spec had some nasty typos, and a large part of the rev0/1 BB
init procedure was also missing. Fix these.

Also make the init-time channel switch debuggable.

(The change from -EINVAL to -EIO is simply to make it possible
to distinguish the PLL charge pump error from a channel-not-found
error.)

Signed-off-by: Gábor Stefanik <netrolller.3d@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>