arm: mxc: Use generic_handle_irq()

	expio_irq = MXC_BOARD_IRQ_START;

	for (; int_valid != 0; int_valid >>= 1, expio_irq++) {

		struct irq_desc *d;

		if ((int_valid & 1) == 0)

			continue;

		d = irq_desc + expio_irq;

		if (unlikely(!(d->handle_irq)))

			pr_err("\nEXPIO irq: %d unhandled\n", expio_irq);

		else

			d->handle_irq(expio_irq, d);

		generic_handle_irq(expio_irq);

	}

	desc->irq_data.chip->irq_ack(&desc->irq_data);