imx: imx6ul: kontron-sl-mx6ul: Enable migrated Kconfig options

The board support was merged at the same time as some Kconfig options
for SPL were migrated/renamed. As a result some essential features
like serial output, MMC support, etc. are currently missing. Fix this
by enabling the required options.

Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
1 file changed