x86: broadwell: Correct I/O APIC ID

Currently ID 2 is assgined to broadwell I/O APIC, however per
chromebook_samus.dts 2 is the core#2 LAPIC ID. Now we change
I/O APIC ID to 4 to avoid conflict.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/cpu/broadwell/pch.c b/arch/x86/cpu/broadwell/pch.c
index f0798a7..317f57d 100644
--- a/arch/x86/cpu/broadwell/pch.c
+++ b/arch/x86/cpu/broadwell/pch.c
@@ -109,7 +109,8 @@
 {
 	u32 reg32;
 
-	io_apic_set_id(0x02);
+	/* Make sure this is a unique ID within system */
+	io_apic_set_id(0x04);
 
 	/* affirm full set of redirection table entries ("write once") */
 	reg32 = io_apic_read(0x01);