irqchip/armada-370-xp: Add Kconfig option for the driver

Instead of building the irq-armada-370-xp driver directly when
CONFIG_ARCH_MVEBU is enabled, this commit introduces an intermediate
CONFIG_ARMADA_370_XP_IRQ hidden Kconfig option.

This allows this option to select other interrupt-related Kconfig
options (which will be needed in follow-up commits) rather than having
such selects done from arch/arm/mach-<foo>/.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Link: https://lkml.kernel.org/r/1455115621-22846-2-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

drivers/irqchip/Kconfig

@@ -60,6 +60,11 @@ config ARM_VIC_NR
 	  The maximum number of VICs available in the system, for
 	  power management.
 
+config ARMADA_370_XP_IRQ
+	bool
+	default y if ARCH_MVEBU
+	select GENERIC_IRQ_CHIP
+
 config ATMEL_AIC_IRQ
 	bool
 	select GENERIC_IRQ_CHIP

drivers/irqchip/Makefile

@@ -5,7 +5,6 @@ obj-$(CONFIG_ARCH_BCM2835)		+= irq-bcm2836.o
 obj-$(CONFIG_ARCH_EXYNOS)		+= exynos-combiner.o
 obj-$(CONFIG_ARCH_HIP04)		+= irq-hip04.o
 obj-$(CONFIG_ARCH_MMP)			+= irq-mmp.o
-obj-$(CONFIG_ARCH_MVEBU)		+= irq-armada-370-xp.o
 obj-$(CONFIG_IRQ_MXS)			+= irq-mxs.o
 obj-$(CONFIG_ARCH_TEGRA)		+= irq-tegra.o
 obj-$(CONFIG_ARCH_S3C24XX)		+= irq-s3c24xx.o
@@ -28,6 +27,7 @@ obj-$(CONFIG_ARM_GIC_V3_ITS)		+= irq-gic-v3-its.o irq-gic-v3-its-pci-msi.o irq-g
 obj-$(CONFIG_HISILICON_IRQ_MBIGEN)	+= irq-mbigen.o
 obj-$(CONFIG_ARM_NVIC)			+= irq-nvic.o
 obj-$(CONFIG_ARM_VIC)			+= irq-vic.o
+obj-$(CONFIG_ARMADA_370_XP_IRQ)		+= irq-armada-370-xp.o
 obj-$(CONFIG_ATMEL_AIC_IRQ)		+= irq-atmel-aic-common.o irq-atmel-aic.o
 obj-$(CONFIG_ATMEL_AIC5_IRQ)	+= irq-atmel-aic-common.o irq-atmel-aic5.o
 obj-$(CONFIG_I8259)			+= irq-i8259.o