configs: ten64: switch to OF_UPSTREAM

configs: ten64: switch to OF_UPSTREAM

Two recent additions to the mainline device tree allow us
to switch away from the local U-Boot copy:

* Board/embedded controller (traverse,ten64-controller)
  is now in the mainline device tree.
* USB Hub (USB5744) connections were also added to
  the mainline device tree but not in U-Boot.

The LS1088A and Ten64 device trees in U-Boot were actually
'synced' to mainline some time ago, so the content
(except for the changes mentioned above) is identical.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Mathew McBride <matt@traverse.com.au>
Signed-off-by: Peng Fan <peng.fan@nxp.com>