* Create virtual peripherals for `ADC`/`DAC`
* Refactor the `analog::dac` module
* Refactor the `analog::adc` module
* Decouple the ADC driver from the `embedded-hal` traits
* Update `CHANGELOG.md`
* Seal the `AdcCalScheme` trait, reduce visibility of `AdcCalEfuse` trait
* Remove `APB_SARADC`/`SENS` peripherals from the `Peripherals` struct
* Provide ADC values in mV instead of requiring the user to scale them
* Changelog
* Try converting poly calibration also
* Update changelog and comments
* Fix example