x86: ivybridge: Add northbridge init functions

Add init for the northbridge, another part of the platform controller hub.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/cpu/ivybridge/bd82x6x.c b/arch/x86/cpu/ivybridge/bd82x6x.c
index 1a3c036..739f979 100644
--- a/arch/x86/cpu/ivybridge/bd82x6x.c
+++ b/arch/x86/cpu/ivybridge/bd82x6x.c
@@ -128,6 +128,8 @@
 
 	bd82x6x_pci_init(PCH_DEV);
 	bd82x6x_sata_enable(PCH_SATA_DEV, blob, sata_node);
+	northbridge_enable(PCH_DEV);
+	northbridge_init(PCH_DEV);
 
 	return 0;
 }