[PATCH] x86: update mptable fix with no ioapic

[Yinghai Lu <yhlu.kernel@gmail.com>]

if the system doesn't have ioapic, we don't need to store entries for mptable
update

Reported-by: Daniel Exner <dex@dragonslave.de>
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>

diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 04dbb35..e639d2f 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -1173,6 +1173,9 @@ int mp_config_acpi_gsi(unsigned char number, unsigned int devfn, u8 pin,
 	if (!enable_update_mptable)
 		return 0;
 
+	if (!acpi_ioapic)
+		return 0;
+
 	/* print the entry should happen on mptable identically */
 	intsrc.mpc_type = MP_INTSRC;
 	intsrc.mpc_irqtype = mp_INT;