AR9170_PWR_REG_PLL_ADDAC is used to set the main clock
divisor which affects the AHB/CPU speed. Because this
would interfere with the firmware internal timekeeping,
the function has to be moved into the firmware.
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>