ARM: SIRF: make sirf irqchip driver optional since new SoCs will have GIC

New MARCO and POLO SoC use GIC, so make irq.c optional and enable it
only if we enable ARCH_PRIMA2 in Kconfig
Signed-off-by: Barry Song <Baohua.Song@csr.com>

arch/arm/mach-prima2/Kconfig

@@ -7,9 +7,13 @@ config ARCH_PRIMA2
 	default y
 	select CPU_V7
 	select ZONE_DMA
+	select SIRF_IRQ
 	help
           Support for CSR SiRFSoC ARM Cortex A9 Platform
 
 endmenu
 
+config SIRF_IRQ
+	bool
+
 endif

arch/arm/mach-prima2/Makefile

 obj-y := timer.o
-obj-y += irq.o
 obj-y += rstc.o
 obj-y += common.o
 obj-y += rtciobrg.o
 obj-$(CONFIG_DEBUG_LL) += lluart.o
 obj-$(CONFIG_CACHE_L2X0) += l2x0.o
 obj-$(CONFIG_SUSPEND) += pm.o sleep.o
+obj-$(CONFIG_SIRF_IRQ) += irq.o

arch/arm/mach-prima2/irq.c

@@ -63,7 +63,7 @@ void __init sirfsoc_of_irq_init(void)
 
 	np = of_find_matching_node(NULL, intc_ids);
 	if (!np)
-		panic("unable to find compatible intc node in dtb\n");
+		return;
 
 	sirfsoc_intc_base = of_iomap(np, 0);
 	if (!sirfsoc_intc_base)