[WCNCR00168085] power-save: add WiFi KeepFullPwr control

[Description]
During airtime utilization and noise histogram collection,
MT7668 will keep in a full power mode.
If enter suspending in that time, the power consumption is high.

[Solution]
Add new CMD_ID_KEEP_FULL_PWR (0x2A) for driver to control KeepFullPwr.
Need the corresponding firmware to handle 0x2A command.

[Test]
1. Passed suspend/resume 50 times and confirm KeepFullPwr is disabled
   when airtime utilization or noise histogram is collecting.
2. Passed 2G/5G AP scan/connection.

Change-Id: I2649ffdbc23a9af29461db37e78dd246453577ee
CR-Id: WCNCR00168085
Feature: power-save
Signed-off-by: ZD Hu <zd.hu@mediatek.com>
5 files changed