regulator: tps6586x: Add and use correct voltage table

Depending on the regulator version, the voltage table might be
different. Use version specific regulator tables in order to select
correct voltage table. For the following regulator versions different
voltage tables are now used:

  * TPS658623: Use correct voltage table for SM2
  * TPS658643: New voltage table for SM2

Both versions are in use on the Colibri T20 module. Make use of the
correct tables by requesting the correct SM2 voltage of 1.8V.

This change is not backward compatible since an old driver is not able
to correctly set that value. The value 1.8V is out of range for the old
driver and will refuse to probe the device. The regulator starts with
default settings and the driver shows appropriate error messages.

On Colibri T20, the old value used to work with TPS658623 since the
driver applied a wrong voltage table too. However, the TPS658643 used
on V1.2 devices uses yet another voltage table and those broke that
pseudo-compatibility. The regulator driver now has the correct voltage
table for both regulator versions and those the correct voltage can be
used in the device tree.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Acked-by: Mark Brown <broonie@linaro.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>