power: regulator: add AXP717 support

The X-Powers AXP717 is a PMIC with four buck converters and a number
of LDOs, one of which is actually fixed (so not modelled here).

Add the compatible string and the respective regulator ranges to allow
drivers to adjust voltages.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Ryan Walklin <ryan@testtoast.com>
3 files changed