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/board/wandboard/wandboard.c b/board/wandboard/wandboard.c
index 5e993d0..c113a0c 100644
--- a/board/wandboard/wandboard.c
+++ b/board/wandboard/wandboard.c
@@ -9,6 +9,7 @@
 #include <common.h>
 #include <image.h>
 #include <init.h>
+#include <log.h>
 #include <asm/arch/clock.h>
 #include <asm/arch/crm_regs.h>
 #include <asm/arch/iomux.h>