bootstage: Replace show_boot_progress/error() with bootstage_...()

These calls should not be made directly any more, since bootstage
will call the show_boot_...() functions as needed.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/lib/bootm.c b/arch/arm/lib/bootm.c
index 249ac1b..f114cd6 100644
--- a/arch/arm/lib/bootm.c
+++ b/arch/arm/lib/bootm.c
@@ -113,7 +113,7 @@
 		printf ("Using machid 0x%x from environment\n", machid);
 	}
 
-	show_boot_progress(BOOTSTAGE_ID_RUN_OS);
+	bootstage_mark(BOOTSTAGE_ID_RUN_OS);
 
 #ifdef CONFIG_OF_LIBFDT
 	if (images->ft_len)