drivers: adc: add DMA support for Silabs IADC

This commit introduces DMA support for the Silabs IADC driver.
A new Kconfig option is added to enable DMA support, ensuring
compatibility with the existing ADC configuration.

DMA can be used for synch/asynch operation.

Signed-off-by: Martin Hoff <martin.hoff@silabs.com>
2 files changed