mfd: stpmic1: move to coredevice level ...

The PMIC provides regulators, which are needed before other
devices can probe.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

mfd: stpmic1: use register define from header ...

A previous commit has copied over the upstream <linux/mfd/stpmic1.h>
header. Use it instead of replicating register definitions in the
MFD and watchdog cell driver. No functional change.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

mfd: stpmic1: use dev_get_regmap instead of priv member ...

When we call regmap_init, the regmap is associated with the device
supplied and can be queried with dev_get_regmap. This is more natural
than expecting cell drivers to cast dev->parent->priv. Do it.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

mfd: add support for STPMIC1 ...

The PMIC is addressable over I2C and, besides power management,
integrates a watchdog, a user power on key handling and 64 bit of
non-volatile memory.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>