cmd: Correct the 'md.q' command

This displays incorrect data at present due to a missing header file
in display_options. Fix it.

Fixes: 0914011310 ("command: Remove the cmd_tbl_t typedef")

Signed-off-by: Simon Glass <sjg@chromium.org>

lib/display_options.c

@@ -5,6 +5,7 @@
  */
 
 #include <common.h>
+#include <compiler.h>
 #include <console.h>
 #include <div64.h>
 #include <version.h>