Merge branch 'feature/disable_phy_rf_when_disable_wifi_bt' into 'master'

disable PHY and RF when stop WiFi and disable BT

1. Add disable PHY and RF when WiFi and BT are both disabled(including call sniffer disable API).

2. Do not init PHY and RF when cpu start. Init PHY and RF when call Wifi or BT start APIs(including sniffer enable API).

3. Add a temporary lib: librtc_clk.a and will delete it when CPU frequency switching function is done.

4. Add an function to get OS tick rate.

5. Do not put the whole pp.a in iram0, only put lmac.o, ieee80211_misc.o, ets_time.o and wdev.o in iram0.

See merge request !510