davinci: da850/omap-l138 evm: account for DEFDCDC{2,3} being tied high

Per the da850/omap-l138 Beta EVM SOM schematic, the DEFDCDC2 and
DEFDCDC3 lines are tied high. This leads to a 3.3V IO and 1.2V CVDD
voltage.

Pass the right platform data to the TPS6507x driver so it can operate
on the DEFDCDC{2,3}_HIGH register to read and change voltage levels.

Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>