ARM64 / ACPI: Enable ARM64 in Kconfig

Add Kconfigs to build ACPI on ARM64, and make ACPI available on ARM64.

acpi_idle driver is x86/IA64 dependent now, so make CONFIG_ACPI_PROCESSOR
depend on X86 || IA64, and implement it on ARM64 in the future.

CC: Rafael J. Wysocki <rjw@rjwysocki.net>
CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Will Deacon <will.deacon@arm.com>
Reviewed-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Tested-by: Yijing Wang <wangyijing@huawei.com>
Tested-by: Mark Langsdorf <mlangsdo@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
Tested-by: Timur Tabi <timur@codeaurora.org>
Tested-by: Robert Richter <rrichter@cavium.com>
Acked-by: Robert Richter <rrichter@cavium.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Graeme Gregory <graeme.gregory@linaro.org>
Signed-off-by: Al Stone <al.stone@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index d00ab9a..e5aa081 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -713,6 +713,8 @@
 
 source "drivers/firmware/Kconfig"
 
+source "drivers/acpi/Kconfig"
+
 source "fs/Kconfig"
 
 source "arch/arm64/kvm/Kconfig"
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index a726381..a8f531e2 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -5,7 +5,7 @@
 menuconfig ACPI
 	bool "ACPI (Advanced Configuration and Power Interface) Support"
 	depends on !IA64_HP_SIM
-	depends on IA64 || X86
+	depends on IA64 || X86 || (ARM64 && EXPERT)
 	depends on PCI
 	select PNP
 	default y
@@ -167,6 +167,7 @@
 	tristate "Processor"
 	select THERMAL
 	select CPU_IDLE
+	depends on X86 || IA64
 	default y
 	help
 	  This driver installs ACPI as the idle handler for Linux and uses