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>

cpuidle: cpuidle-cps: Enable use with MIPSr6 CPUs.

This patch enables the MIPS CPS driver for MIPSr6 CPUs.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: linux-mips@linux-mips.org
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14228/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Kconfig: Add missing MIPS_CPS dependencies to PM and cpuidle

The MIPS_CPS_PM and MIPS_CPS_CPUIDLE implementation should depend
on the MIPS_CPS symbol to avoid the following build problem

arch/mips/kernel/pm-cps.c: In function 'cps_pm_enter_state':
arch/mips/kernel/pm-cps.c:164:26: error: 'cpu_coherent_mask' undeclared
(first use in this function)
cpumask_clear_cpu(cpu, &cpu_coherent_mask);
^
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/7798/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

cpuidle: cpuidle-cps: add MIPS CPS cpuidle driver

This patch adds a cpuidle driver for systems based around the MIPS
Coherent Processing System (CPS) architecture. It supports four idle
states:

- The standard MIPS wait instruction.

- The non-coherent wait, clock gated & power gated states exposed by
the recently added pm-cps layer.

The pm-cps layer is used to enter all the deep idle states. Since cores
in the clock or power gated states cannot service interrupts, the
gic_send_ipi_single function is modified to send a power up command for
the appropriate core to the CPC in cases where the target CPU has marked
itself potentially incoherent.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>