1. raise vddsdio for 1.8v flash
2. gpio matrix config for flash
3. fix esp_restart function
todo:
to decide whether to raise core voltage
to test deep-sleep current
Also add steps to disable flash encryption, as some people seem to
accidentally enable it.
Explicitly mark the flash encryption and secure boot as "READ DOCS
FIRST" in menuconfig.
* App access functions are all flash encryption-aware
* Documentation for flash encryption
* Partition read/write is flash aware
* New encrypted write function
This also removes logging implementation from bootloader and replaces it
with the one provided by the log component. Some occurrences of printf
and ets_printf have been changed to ESP_LOGx APIs.
