If this variable is not set in the config it may contain random data and set the clock source to the REF_CLK
resulting in timing errors, the DHTx, DS18B20 and ws2812 devices to not communicate.
The uzlib and parts of Lua had to be switched over to use the
C standard int types, as their custom typedefs conflicted with
RISC-V toolchain provided typedefs.
UART console driver updated to do less direct register meddling
and use the IDF uart driver interface for setup. Still using our
own ISR rather than the default driver ISR. Down the line we
might want to investigate whether the IDF ISR would be a better
fit.
Lua C modules have been split into common and ESP32/ESP32-S
specific ones. In the future there might also be ESP32-C3
specific modules, which would go into components/modules-esp32c3
at that point.
Our old automatic fixup of flash size has been discarded as it
interferes with the checksumming done by the ROM loader and
results in unbootable systems. The IDF has already taken on
this work via the ESPTOOL_FLASHSIZE_DETECT option, which handles
this situation properly.