genirq: remove irq_to_desc_alloc

Remove the leftover of sparseirqs.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/io_apic.c

@@ -1257,11 +1257,7 @@ static void ioapic_register_intr(int irq, unsigned long trigger)
 {
 	struct irq_desc *desc;
 
-	/* first time to use this irq_desc */
-	if (irq < 16)
-		desc = irq_to_desc(irq);
-	else
-		desc = irq_to_desc_alloc(irq);
+	desc = irq_to_desc(irq);
 
 	if ((trigger == IOAPIC_AUTO && IO_APIC_irq_trigger(irq)) ||
 	    trigger == IOAPIC_LEVEL)

arch/x86/kernel/irqinit_32.c

@@ -70,7 +70,7 @@ void __init init_ISA_irqs (void)
 	 */
 	for (i = 0; i < 16; i++) {
 		/* first time call this irq_desc */
-		struct irq_desc *desc = irq_to_desc_alloc(i);
+		struct irq_desc *desc = irq_to_desc(i);
 
 		desc->status = IRQ_DISABLED;
 		desc->action = NULL;

arch/x86/kernel/irqinit_64.c

@@ -144,7 +144,7 @@ void __init init_ISA_irqs(void)
 
 	for (i = 0; i < 16; i++) {
 		/* first time call this irq_desc */
-		struct irq_desc *desc = irq_to_desc_alloc(i);
+		struct irq_desc *desc = irq_to_desc(i);
 
 		desc->status = IRQ_DISABLED;
 		desc->action = NULL;

include/linux/irq.h

@@ -210,11 +210,6 @@ static inline struct irq_desc *irq_to_desc(unsigned int irq)
 	return (irq < nr_irqs) ? irq_desc + irq : NULL;
 }
 
-static inline struct irq_desc *irq_to_desc_alloc(unsigned int irq)
-{
-	return irq_to_desc(irq);
-}
-
 #ifdef CONFIG_HAVE_DYN_ARRAY
 #define kstat_irqs_this_cpu(DESC) \
 	((DESC)->kstat_irqs[smp_processor_id()])

kernel/irq/chip.c

@@ -28,7 +28,7 @@ void dynamic_irq_init(unsigned int irq)
 	unsigned long flags;
 
 	/* first time to use this irq_desc */
-	desc = irq_to_desc_alloc(irq);
+	desc = irq_to_desc(irq);
 	if (!desc) {
 		WARN(1, KERN_ERR "Trying to initialize invalid IRQ%d\n", irq);
 		return;