ath9k_hw: Add register definitions for WoW support

*MAC WoW registers

back-off shift, MAC interrupt enable, magic packet enable,
pattern match enable, aifs, slot wait period, keep alive
frame failure count, beacon fail enable, beacon timeout,
keep alive timeout, auto keep alive disable,
keep alive fail disable and their corresponding
status registers. keep alive frame delay,
pattern end/byte offsets, transmit buffers for
keep alive frames and storing the user patterns

*Power Management Control registers

pme_d3cold_vaux, host_pme_enable, aux_pwr_detect,
power_state_mask, wow_pme_clear

Cc: Senthil Balasubramanian <senthilb@qca.qualcomm.com>
Cc: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Cc: vadivel@qca.qualcomm.com
Signed-off-by: Luis R. Rodriguez <mcgrof@qca.qualcomm.com>
Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>