boards: nxp: frdm_mcxe31b: Enable SAR ADC support

1. Enable SAR ADC support for nxp mcxe31x platform.
2. Enable SAR ADC support for nxp frdm_mcxe31b board.

Signed-off-by: Zhaoxiang Jin <Zhaoxiang.Jin_1@nxp.com>
3 files changed