x86/hpet: Use new irqdomain interfaces to allocate/free IRQ

Use new irqdomain interfaces to allocate/free IRQ for HPET, so we can
remove GENERIC_IRQ_LEGACY_ALLOC_HWIRQ later.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Cohen <david.a.cohen@linux.intel.com>
Cc: Sander Eikelenboom <linux@eikelenboom.it>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/1416894816-23245-4-git-send-email-jiang.liu@linux.intel.comSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/hpet.c

@@ -11,6 +11,7 @@
 #include <linux/cpu.h>
 #include <linux/pm.h>
 #include <linux/io.h>
+#include <linux/irqdomain.h>
 
 #include <asm/fixmap.h>
 #include <asm/hpet.h>
@@ -476,7 +477,7 @@ 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)) {
-		irq_free_hwirq(irq);
+		irq_domain_free_irqs(irq, 1);
 		return -EINVAL;
 	}
 	return 0;
@@ -484,9 +485,10 @@ static int hpet_setup_msi_irq(unsigned int irq)
 
 static int hpet_assign_irq(struct hpet_dev *dev)
 {
-	unsigned int irq = irq_alloc_hwirq(-1);
+	int irq;
 
-	if (!irq)
+	irq = irq_domain_alloc_irqs(NULL, 1, NUMA_NO_NODE, NULL);
+	if (irq <= 0)
 		return -EINVAL;
 
 	irq_set_handler_data(irq, dev);