irq_domain/powerpc: Use common irq_domain structure instead of irq_host

This patch drops the powerpc-specific irq_host structures and uses the common
irq_domain strucutres defined in linux/irqdomain.h.  It also fixes all
the users to use the new structure names.

Renaming irq_host to irq_domain has been discussed for a long time, and this
patch is a step in the process of generalizing the powerpc virq code to be
usable by all architecture.

An astute reader will notice that this patch actually removes the irq_host
structure instead of renaming it.  This is because the irq_domain structure
already exists in include/linux/irqdomain.h and has the needed data members.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>

arch/powerpc/platforms/ps3/interrupt.c

@@ -667,7 +667,7 @@ static void __maybe_unused _dump_mask(struct ps3_private *pd,
 static void dump_bmp(struct ps3_private* pd) {};
 #endif /* defined(DEBUG) */
 
-static int ps3_host_map(struct irq_host *h, unsigned int virq,
+static int ps3_host_map(struct irq_domain *h, unsigned int virq,
 	irq_hw_number_t hwirq)
 {
 	DBG("%s:%d: hwirq %lu, virq %u\n", __func__, __LINE__, hwirq,
@@ -678,13 +678,13 @@ static int ps3_host_map(struct irq_host *h, unsigned int virq,
 	return 0;
 }
 
-static int ps3_host_match(struct irq_host *h, struct device_node *np)
+static int ps3_host_match(struct irq_domain *h, struct device_node *np)
 {
 	/* Match all */
 	return 1;
 }
 
-static struct irq_host_ops ps3_host_ops = {
+static struct irq_domain_ops ps3_host_ops = {
 	.map = ps3_host_map,
 	.match = ps3_host_match,
 };
@@ -751,9 +751,9 @@ void __init ps3_init_IRQ(void)
 {
 	int result;
 	unsigned cpu;
-	struct irq_host *host;
+	struct irq_domain *host;
 
-	host = irq_alloc_host(NULL, IRQ_HOST_MAP_NOMAP, 0, &ps3_host_ops,
+	host = irq_alloc_host(NULL, IRQ_DOMAIN_MAP_NOMAP, 0, &ps3_host_ops,
 		PS3_INVALID_OUTLET);
 	irq_set_default_host(host);
 	irq_set_virq_count(PS3_PLUG_MAX + 1);