[U-Boot] Falcon mode for TI DM355

[Andy Pont]

Hi Tom,

> So, git commit 6761946f is what removed the board in question.  Now,
> looking in mainline today (and also looking at 6761946f) I see that we
> had and have support for CONFIG_TARGET_OMAPL138_LCDK and that uses SPL
> which is a prerequisite for falcon mode.  So there's nothing too low
> level that would need to be done for the DM355, just the board specific
> portions.

The current implementation for the target hardware is based on 2013.07.  Can
we make it work with that or should we look to move to something more
recent?  Not wanting to make too many changes unnecessarily.

Andy.