genpd: Create a new subsystem directory to host genpd providers

There are currently ~60 users of the genpd provider interface, which
implementations are sprinkled across various subsystems. To simplify with
maintenance let's create a new subsystem (drivers/genpd) and start moving
the providers in there.

My intention is also to host a git tree to collect and to get the patches
tested/integrated through the linux-next tree. Ideally this should release
some of the burden on the soc maintainers.

Note that, I will of course require acks/reviews from the current platform
maintainers, hence the MAINTAINERS file needs to be updated accordingly for
each genpd provider that is moved into the new genpd subsystem.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

MAINTAINERS

@@ -8665,6 +8665,13 @@ F:	Documentation/devicetree/bindings/power/power?domain*
 F:	drivers/base/power/domain*.c
 F:	include/linux/pm_domain.h
 
+GENERIC PM DOMAIN PROVIDERS
+M:	Ulf Hansson <ulf.hansson@linaro.org>
+L:	linux-pm@vger.kernel.org
+S:	Supported
+T:	git git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/linux-pm.git
+F:	drivers/genpd/
+
 GENERIC RESISTIVE TOUCHSCREEN ADC DRIVER
 M:	Eugen Hristev <eugen.hristev@microchip.com>
 L:	linux-input@vger.kernel.org

drivers/Makefile

@@ -45,6 +45,7 @@ obj-$(CONFIG_DMADEVICES)	+= dma/
 
 # SOC specific infrastructure drivers.
 obj-y				+= soc/
+obj-$(CONFIG_PM_GENERIC_DOMAINS)	+= genpd/
 
 obj-y				+= virtio/
 obj-$(CONFIG_VDPA)		+= vdpa/

drivers/genpd/Makefile

+# SPDX-License-Identifier: GPL-2.0-only