irqchip: Define EXYNOS_IRQ_COMBINER

This patch is written to clean up dependency of ARCH_EXYNOS
Not all exynos device have IRQ_COMBINER, especially aarch64 EXYNOS
but it is built for all exynos devices.
Thus add the config for EXYNOS_IRQ_COMBINER
remove direct dependency between ARCH_EXYNOS and exynos-combiner.c
and only selected on the aarch32 devices

Signed-off-by: Hyunki Koo <hyunki00.koo@samsung.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20191224211108.7128-1-hyunki00.koo@gmail.com

arch/arm/mach-exynos/Kconfig

@@ -12,6 +12,7 @@ menuconfig ARCH_EXYNOS
 	select ARCH_SUPPORTS_BIG_ENDIAN
 	select ARM_AMBA
 	select ARM_GIC
+	select EXYNOS_IRQ_COMBINER
 	select COMMON_CLK_SAMSUNG
 	select EXYNOS_ASV
 	select EXYNOS_CHIPID

drivers/irqchip/Kconfig

@@ -500,4 +500,11 @@ config SIFIVE_PLIC
 
 	   If you don't know what to do here, say Y.
 
+config EXYNOS_IRQ_COMBINER
+	bool "Samsung Exynos IRQ combiner support" if COMPILE_TEST
+	depends on (ARCH_EXYNOS && ARM) || COMPILE_TEST
+	help
+	  Say yes here to add support for the IRQ combiner devices embedded
+	  in Samsung Exynos chips.
+
 endmenu

drivers/irqchip/Makefile

@@ -9,7 +9,7 @@ obj-$(CONFIG_ARCH_BCM2835)		+= irq-bcm2835.o
 obj-$(CONFIG_ARCH_BCM2835)		+= irq-bcm2836.o
 obj-$(CONFIG_DAVINCI_AINTC)		+= irq-davinci-aintc.o
 obj-$(CONFIG_DAVINCI_CP_INTC)		+= irq-davinci-cp-intc.o
-obj-$(CONFIG_ARCH_EXYNOS)		+= exynos-combiner.o
+obj-$(CONFIG_EXYNOS_IRQ_COMBINER)	+= exynos-combiner.o
 obj-$(CONFIG_FARADAY_FTINTC010)		+= irq-ftintc010.o
 obj-$(CONFIG_ARCH_HIP04)		+= irq-hip04.o
 obj-$(CONFIG_ARCH_LPC32XX)		+= irq-lpc32xx.o