udoo_neo: Select DM_SERIAL and drop iomux board level init

Convert to DM_SERIAL and drop the iomux board file
level init as it's handled as part of the DM serial
layer instead.

Signed-off-by: Peter Robinson <pbrobinson@gmail.com>
Reviewed-by: Fabio Estevam <festevam@denx.de>
2 files changed