[MIPS] Lasat: Fix build by conversion to irq_cpu.c.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index f921235..235d451 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -133,6 +133,7 @@
 	select DMA_NONCOHERENT
 	select SYS_HAS_EARLY_PRINTK
 	select HW_HAS_PCI
+	select IRQ_CPU
 	select PCI_GT64XXX_PCI0
 	select MIPS_NILE4
 	select R5000_CPU_SCACHE