b43: Fix typo in function name

[Kalle Valo]

> This fixes a typo in the "b43_lo_g_maintenance_work" function
> name.
> 
> Signed-off-by: Nik Nyby <nikolas at gnu.org>
> Acked-by: Larry Finger <Larry.Finger at lwfinger.net>
> Acked-by: Michael Buesch <m at bues.ch>

Thanks, applied to wireless-drivers-next.git.

Kalle Valo