verdin-imx8mm: spl: enable pca9450 i2c level translator

Enable PCA9450 i2c level translator, as this is used for the
on module ADC.

Signed-off-by: Max Krummenacher <max.krummenacher@toradex.com>
Acked-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Reviewed-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>