x86: probe nr_irqs even only mptable is used

for !CONFIG_HAVE_SPARSE_IRQ

fix:

 In file included from arch/x86/kernel/early-quirks.c:18:
 include/asm/io_apic.h: In function 'probe_nr_irqs':
 include/asm/io_apic.h:209: error: 'NR_IRQS' undeclared (first use in this function)
 include/asm/io_apic.h:209: error: (Each undeclared identifier is reported only once
 include/asm/io_apic.h:209: error: for each function it appears in.)

v2: fix by Ingo

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/io_apic.c b/arch/x86/kernel/io_apic.c
index f853b66..f7e8026 100644
--- a/arch/x86/kernel/io_apic.c
+++ b/arch/x86/kernel/io_apic.c
@@ -3596,6 +3596,36 @@
 }
 #endif /* CONFIG_HT_IRQ */
 
+int __init io_apic_get_redir_entries (int ioapic)
+{
+	union IO_APIC_reg_01	reg_01;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ioapic_lock, flags);
+	reg_01.raw = io_apic_read(ioapic, 1);
+	spin_unlock_irqrestore(&ioapic_lock, flags);
+
+	return reg_01.bits.entries;
+}
+
+int __init probe_nr_irqs(void)
+{
+	int idx;
+	int nr = 0;
+
+	for (idx = 0; idx < nr_ioapics; idx++)
+		nr += io_apic_get_redir_entries(idx);
+
+	/* double it for hotplug and msi and nmi */
+	nr <<= 1;
+
+	/* something wrong ? */
+	if (nr < 32)
+		nr = 32;
+
+	return nr;
+}
+
 /* --------------------------------------------------------------------------
                           ACPI-based IOAPIC Configuration
    -------------------------------------------------------------------------- */
@@ -3690,19 +3720,6 @@
 }
 #endif
 
-int __init io_apic_get_redir_entries (int ioapic)
-{
-	union IO_APIC_reg_01	reg_01;
-	unsigned long flags;
-
-	spin_lock_irqsave(&ioapic_lock, flags);
-	reg_01.raw = io_apic_read(ioapic, 1);
-	spin_unlock_irqrestore(&ioapic_lock, flags);
-
-	return reg_01.bits.entries;
-}
-
-
 int io_apic_set_pci_routing (int ioapic, int pin, int irq, int triggering, int polarity)
 {
 	if (!IO_APIC_IRQ(irq)) {