Add boundary/nw board

Signed-off-by: Eric Nelson <eric.nelson@boundarydevices.com>
nw: Don't include NET commands
nw: only support mmc 0
nw: no USB Host ethernet on NW board (requires networking)

Signed-off-by: Eric Nelson <eric.nelson@boundarydevices.com>
nw: set up USB OTG pads

Signed-off-by: Eric Nelson <eric.nelson@boundarydevices.com>