Update adc drivers to use DT_HAS_<compat>_ENABLED Kconfig symbol
to expose the driver and enable it by default based on devicetree.
We remove 'depend on' Kconfig for symbols that would be implied by
the devicetree node existing.
Signed-off-by: Kumar Gala <galak@kernel.org>
Add a dummy driver for the `vnd,adc` compatible to allow compilation of
drivers utilising an ADC when running "build_all" tests.
Signed-off-by: Jordan Yates <jordan.yates@data61.csiro.au>