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/cmd/elf.c b/cmd/elf.c
index 4f2969a..d44b95d 100644
--- a/cmd/elf.c
+++ b/cmd/elf.c
@@ -10,6 +10,7 @@
 #include <elf.h>
 #include <env.h>
 #include <image.h>
+#include <log.h>
 #include <net.h>
 #include <vxworks.h>
 #ifdef CONFIG_X86