This adds the base addresses of i.MX23 and easy the detection of wrong
order in board setup, in case no SoC has been set, an error is raised
during build.

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Stefano Babic <sbabic@denx.de>