Initialize the pmu sleep machine constant when pmu is initialized, and calculate
the pmu sleep time adjustment value and hardware configuration value according
to the machine constant during system sleep.
Calibrate fast OSC before each sleep and use the calibration value to calculate
PMU hardware wait cycles when use the fast OSC as the work clock.
- Support SOC ROOT clock source switch
- Support CPU frequency change
- Support RTC SLOW clock source switch
- Support RTC SLOW clock + RC FAST calibration
Remove FPGA build for esp32c6
