ath9k_hw: Initvals update for AR9462

MSI is enabled by default for most of the 4th generation
chips. Add this for AR9462 - this fixes PowerSave operation,
the chip was not entering Network-Sleep mode earlier.
With proper powering down of the MAC now, power consumption
in associated state is reduced considerably.
Signed-off-by: NSujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/ar9462_2p0_initvals.h

@@ -1007,6 +1007,7 @@ static const u32 ar9462_2p0_radio_core[][2] = {
 
 static const u32 ar9462_2p0_soc_preamble[][2] = {
 	/* Addr      allmodes  */
+	{0x000040a4 ,0x00a0c1c9},
 	{0x00007020, 0x00000000},
 	{0x00007034, 0x00000002},
 	{0x00007038, 0x000004c2},