[MIPS] Fix return type of gt64120_irq.

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

arch/mips/gt64120/common/time.c

@@ -20,7 +20,7 @@
  * differently than other MIPS interrupts.
  */
 
-static void gt64120_irq(int irq, void *dev_id)
+static irqreturn_t gt64120_irq(int irq, void *dev_id)
 {
 	unsigned int irq_src, int_high_src, irq_src_mask, int_high_src_mask;
 	int handled = 0;
@@ -43,6 +43,8 @@ static void gt64120_irq(int irq, void *dev_id)
 
 	GT_WRITE(GT_INTRCAUSE_OFS, 0);
 	GT_WRITE(GT_HINTRCAUSE_OFS, 0);
+
+	return IRQ_HANDLED;
 }
 
 /*