x86: hpet: Use irq_alloc/free_hwirq()

Use the new interfaces. No functional change.

This does not replace the requirement to move x86 to irq domains, but
it limits the mess to some degree.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NGrant Likely <grant.likely@linaro.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20140507154334.991589924@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/hpet.c

@@ -479,7 +479,7 @@ static int hpet_msi_next_event(unsigned long delta,
 static int hpet_setup_msi_irq(unsigned int irq)
 {
 	if (x86_msi.setup_hpet_msi(irq, hpet_blockid)) {
-		destroy_irq(irq);
+		irq_free_hwirq(irq);
 		return -EINVAL;
 	}
 	return 0;
@@ -487,9 +487,8 @@ static int hpet_setup_msi_irq(unsigned int irq)
 
 static int hpet_assign_irq(struct hpet_dev *dev)
 {
-	unsigned int irq;
+	unsigned int irq = irq_alloc_hwirq(-1);
 
-	irq = create_irq_nr(0, -1);
 	if (!irq)
 		return -EINVAL;