Update gpio 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 check to see that the GPIO devicetree node is actually enabled
before we build the PSoC6 GPIO driver.
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>