rtw88: decide lps deep mode from firmware feature.

This patch checks the supported lps deep mode from firmware feature,
and allows different firmware have different deep power mode.
Original module parameter rtw_fw_lps_deep_mode is replaced with
rtw_disable_lps_deep_mode for user to disable lps deep mode.

Signed-off-by: Chin-Yen Lee <timlee@realtek.com>
Signed-off-by: Tzu-En Huang <tehuang@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20201030084826.9034-5-tehuang@realtek.com