ath9k_hw: Enable hw PLL power save for AR9462

ath9k_hw: Enable hw PLL power save for AR9462

commit 1680260226a8fd2aab590319da83ad8e610da9bd upstream.

This reduced the power consumption to half in full and network sleep.

Cc: Paul Stewart <pstew@chromium.org>
Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
[bwh: Backported to 3.2:
 - INIT_INI_ARRAY macro requires an explicit size argument
 - Remove the now-redundant macro PCIE_PLL_ON_CREQ_DIS_L1_2P0]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>