x86: Emit port 80 post codes in show_boot_progress()

This helps us monitor boot progress and determine where U-Boot dies if
there are any problems.

Signed-off-by: Stefan Reinauer <reinauer@google.com>

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/configs/coreboot.h b/include/configs/coreboot.h
index e45ecad..94b6917 100644
--- a/include/configs/coreboot.h
+++ b/include/configs/coreboot.h
@@ -35,7 +35,7 @@
  * (easy to change)
  */
 #define CONFIG_SYS_COREBOOT
-#undef CONFIG_SHOW_BOOT_PROGRESS
+#define CONFIG_SHOW_BOOT_PROGRESS
 #define CONFIG_LAST_STAGE_INIT
 #define CONFIG_X86_NO_RESET_VECTOR
 #define CONFIG_SYS_VSNPRINTF