x86/ioapic: Simplify ioapic_setup_resources()

Optimize the function by removing the variable 'num'.

Signed-off-by: Rui Wang <rui.y.wang@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: tony.luck@intel.com
Cc: linux-pci@vger.kernel.org
Cc: rjw@rjwysocki.net
Cc: linux-acpi@vger.kernel.org
Cc: bhelgaas@google.com
Link: http://lkml.kernel.org/r/1465369193-4816-4-git-send-email-rui.y.wang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/kernel/apic/io_apic.c

@@ -2567,29 +2567,25 @@ static struct resource * __init ioapic_setup_resources(void)
 	unsigned long n;
 	struct resource *res;
 	char *mem;
-	int i, num = 0;
+	int i;
 
-	for_each_ioapic(i)
-		num++;
-	if (num == 0)
+	if (nr_ioapics == 0)
 		return NULL;
 
 	n = IOAPIC_RESOURCE_NAME_SIZE + sizeof(struct resource);
-	n *= num;
+	n *= nr_ioapics;
 
 	mem = alloc_bootmem(n);
 	res = (void *)mem;
 
-	mem += sizeof(struct resource) * num;
+	mem += sizeof(struct resource) * nr_ioapics;
 
-	num = 0;
 	for_each_ioapic(i) {
-		res[num].name = mem;
-		res[num].flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+		res[i].name = mem;
+		res[i].flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 		snprintf(mem, IOAPIC_RESOURCE_NAME_SIZE, "IOAPIC %u", i);
 		mem += IOAPIC_RESOURCE_NAME_SIZE;
-		ioapics[i].iomem_res = &res[num];
-		num++;
+		ioapics[i].iomem_res = &res[i];
 	}
 
 	ioapic_resources = res;