arm/dts: regulator: Add tps65910 device tree data

Add device tree data for tps65910 regulator by adding all tps65910
regulator nodes. Regulator is initialized based on compatiable
name provided in tps65910 DT file.

All tps65910 PMIC regulator device tree nodes are placed in a
seperate device tree include file (tps65910.dtsi). This patch
was tested on AM335x-EVM.

Signed-off-by: AnilKumar Ch <anilkumar@ti.com>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>