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/drivers/usb/eth/lan78xx.c b/drivers/usb/eth/lan78xx.c
index fe8cc6a..1d1b64e 100644
--- a/drivers/usb/eth/lan78xx.c
+++ b/drivers/usb/eth/lan78xx.c
@@ -4,6 +4,7 @@
  */
 
 #include <dm.h>
+#include <log.h>
 #include <net.h>
 #include <usb.h>
 #include "usb_ether.h"