DT: add binding for mxs power subsystem

This patch adds the device tree bindings for the Freescale MXS
power subsystem.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
power: mxs_power: add driver for mxs power subsystem

This patch adds a minimal driver for the Freescale i.MX23, i.MX28
power subsystem. It's required to trigger the probing of the underlying
drivers like on-chip regulators. Additionally the drivers supports
the configuration of the DC-DC clock frequency to avoid possible
interferences.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
ARM: dts: enable power subsystem for i.MX28

This patch enables the power subsystem for all i.MX28 boards.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
ARM: dts: enable power subsystem for i.MX23

This patch enables the power subsystem for all i.MX23 boards.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>