irqchip/ts4800: Add hardware dependency

The Technologic Systems TS-4800 is an i.MX515 board, so its drivers
are useless unless building a SOC_IMX51 kernel, except for build
testing purposes.
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Cc: Damien Riegel <damien.riegel@savoirfairelinux.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/20160209111920.1ec318bd@endymionSigned-off-by: NJason Cooper <jason@lakedaemon.net>

drivers/irqchip/Kconfig

@@ -165,6 +165,7 @@ config TS4800_IRQ
 	tristate "TS-4800 IRQ controller"
 	select IRQ_DOMAIN
 	depends on HAS_IOMEM
+	depends on SOC_IMX51 || COMPILE_TEST
 	help
 	  Support for the TS-4800 FPGA IRQ controller