treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mfd: Add lp8788 mfd driver

TI LP8788 PMU provides regulators, battery charger, ADC,
RTC, backlight driver and current sinks.

This MFD patch supports the I2C communication using the regmap,
the interrupt handling using the linear IRQ domain and
configurable platform data structures for each driver module.

(Driver Architecture)

< mfd devices >
LP8788 HW .......... mfd .......... regulator drivers
I2C power supply driver
IRQs iio adc driver
rtc driver
backlight driver
current sink drivers

o regulators : LDOs and BUCKs
o power supply : Battery charger
o iio adc : Battery voltage/temperature
o rtc : RTC and alarm
o backlight
o current sink : LED and vibrator

All MFD device modules are registered by LP8788 MFD core driver.
For sharing information such like the virtual IRQ number,
MFD core driver uses the resource structure.
Then each module can retrieve the specific IRQ number and detect it
in the IRQ thread.

Configurable platform data is handled in each driver module.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>