x86/htirq: Create named domain

Use the fwnode to create a named domain so diagnosis works.

Mark the init function __init while at it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/20170619235443.829047007@linutronix.deSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/apic/htirq.c

@@ -150,16 +150,27 @@ static const struct irq_domain_ops htirq_domain_ops = {
 	.deactivate	= htirq_domain_deactivate,
 };
 
-void arch_init_htirq_domain(struct irq_domain *parent)
+void __init arch_init_htirq_domain(struct irq_domain *parent)
 {
+	struct fwnode_handle *fn;
+
 	if (disable_apic)
 		return;
 
-	htirq_domain = irq_domain_add_tree(NULL, &htirq_domain_ops, NULL);
+	fn = irq_domain_alloc_named_fwnode("PCI-HT");
+	if (!fn)
+		goto warn;
+
+	htirq_domain = irq_domain_create_tree(fn, &htirq_domain_ops, NULL);
+	irq_domain_free_fwnode(fn);
 	if (!htirq_domain)
-		pr_warn("failed to initialize irqdomain for HTIRQ.\n");
-	else
-		htirq_domain->parent = parent;
+		goto warn;
+
+	htirq_domain->parent = parent;
+	return;
+
+warn:
+	pr_warn("Failed to initialize irqdomain for HTIRQ.\n");
 }
 
 int arch_setup_ht_irq(int idx, int pos, struct pci_dev *dev,