common: Drop bootstage.h from common header

Move this fairly uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/common/cli.c b/common/cli.c
index 38bba17..e5e5894 100644
--- a/common/cli.c
+++ b/common/cli.c
@@ -9,6 +9,7 @@
  */
 
 #include <common.h>
+#include <bootstage.h>
 #include <cli.h>
 #include <cli_hush.h>
 #include <command.h>