layerscape: remove Traverse LS1043 boards

layerscape: remove Traverse LS1043 boards

The Traverse LS1043 boards were not publicly released,
all the production has been going to OEM customers who
do not use the image format defined in the OpenWrt tree.

Only a few samples were circulated outside Traverse
and our OEM customers. The public release (then called
Five64) of this series was cancelled in favour of our
LS1088A based design (Ten64).

It is best to remove these boards to avoid wasting
OpenWrt project and contributor resources.

Signed-off-by: Mathew McBride <matt@traverse.com.au>
(cherry picked from commit 8e7ba6fbae80838c2219ee38307af9c883606c2c)