LDO8 of Palma device like tps65913 support the tracking mode
on which LDO8 track the SMPS45 voltage when SMPS45 is ON
and use the LDO8.VOLTAGE_SEL register when SMPS45 is OFF.

On track mode, the steps of voltage change for LDO8 is 25mV
where in non-tracking mode it is 50mV. Set the steps accordingly.
Number of voltage count is still same for both the cases.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Acked-by: Graeme Gregory <gg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>