common: Drop log.h from common header

Move this header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/cpu/ivybridge/northbridge.c b/arch/x86/cpu/ivybridge/northbridge.c
index 0f427af..877b31b 100644
--- a/arch/x86/cpu/ivybridge/northbridge.c
+++ b/arch/x86/cpu/ivybridge/northbridge.c
@@ -8,6 +8,7 @@
 
 #include <common.h>
 #include <dm.h>
+#include <log.h>
 #include <asm/msr.h>
 #include <asm/cpu.h>
 #include <asm/intel_regs.h>