regulator: TPS65910: Create an array for init data

Create an array of fixed size for the platform to pass regulator
initalization data through.

Passing an array of pointers to init data also allows more flexible
definition of init data as well as prevents reading past the end of the
array should the platform define an incorrectly sized array.

Signed-off-by: Kyle Manna <kyle.manna@fuel7.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>