brcmsmac: correct phy registers for TSSI-based power control

A number of additional phy registers needs to be programmed when
using TSSI-based power control.

Tested-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>