[MIPS] Rewrite spurious_interrupt from assembler to C.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/include/asm-mips/irq.h b/include/asm-mips/irq.h
index 8a342cc..d7aecca 100644
--- a/include/asm-mips/irq.h
+++ b/include/asm-mips/irq.h
@@ -46,5 +46,6 @@
 #endif
 
 extern void arch_init_irq(void);
+extern void spurious_interrupt(struct pt_regs *regs);
 
 #endif /* _ASM_IRQ_H */