This brings in the new ADC api for STM32 parts.
Update to new standardized ADC apis.
Drops pointless channel definitions, uses common names for common functions.
No functional changes.
Based on work in: https://github.com/libopencm3/libopencm3-examples/pull/130
While some of the examples include a "board.ld" style file, some of them were
pointing to the libopencm3 provided chip specific ld scripts. When
TOOLCHAIN_DIR has been overridden, those paths were no longer valid/correct.
My bad, I'd been testing my header includes against a branch with some
draft unification of the adc code. ADC is one of the remaining major
peripherals that isn't unified neatly.
Replace includes of stm32/YY/xxxx.h with stm32/xxxx.h
Replace stm32/YY/nvic.h with cm3/nvic.h.
In some cases, the include list was resorted alphabetically when it was
complicated and I was reviewing them manually, but most of this was
automatically done.
