treewide: Add SPDX license identifier - Makefile/Kconfig

Add SPDX license identifiers to all Make/Kconfig files which:

- Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

HSI: cmt_speech: Add cmt-speech driver

Introduces the cmt-speech driver, which implements
a character device interface for transferring speech
data frames over HSI/SSI.

The driver is used to exchange voice/speech data between
the Nokia N900/N950/N9's modem and its cpu.

Signed-off-by: Kai Vehmanen <kai.vehmanen@nokia.com>
Signed-off-by: Carlos Chinea <carlos.chinea@nokia.com>
Signed-off-by: Joni Lapilainen <joni.lapilainen@gmail.com>

Since the original driver has been written for 2.6.28 some
build fixes and general cleanups have been added by me:

* fix build for 4.0 kernel
* replace GFP_ATOMIC with GFP_KERNEL in cs_alloc_cmds()
* add sanity check for CS_SET_WAKELINE ioctl
* cleanup driver initialisation
* rename driver to cmt-speech to be consistent with
ssi-protocol driver
* move cs-protocol.h to include/uapi/linux/hsi, since
it describes a userspace API
* replace hardcoded channels numbers with values provided
via the HSI framework (e.g. coming from DT)

Acked-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Tested-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Sebastian Reichel <sre@kernel.org>

HSI: Introduce Nokia N900 modem driver

The Nokia N900's modem is connected via Synchronous Serial Interface (SSI),
which is a legacy version of MIPI's High-speed Synchronous Serial Interface
(HSI).

The handles the GPIOs for enabling and resetting the modem and instanciates
ssi-protocol for data exchange. It does not yet support exchanging voice data
with the modem.

Signed-off-by: Sebastian Reichel <sre@kernel.org>
Reviewed-by: Pavel Machek <pavel@ucw.cz>
Tested-By: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>

HSI: Introduce driver for SSI Protocol

This adds a driver for the SSI McSAAB protocol as used in
the Nokia N900.

Signed-off-by: Carlos Chinea <carlos.chinea@nokia.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Tested-By: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>

HSI: hsi_char: Add HSI char device kernel configuration

Add HSI character device kernel configuration

Signed-off-by: Andras Domokos <andras.domokos@nokia.com>
Signed-off-by: Carlos Chinea <carlos.chinea@nokia.com>