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/post/post.c b/post/post.c
index 9579a94..7c2bdf0 100644
--- a/post/post.c
+++ b/post/post.c
@@ -158,7 +158,7 @@
 				post_log("PASSED\n");
 			else {
 				post_log("FAILED\n");
-				show_boot_error(BOOTSTAGE_ID_POST_FAIL_R);
+				bootstage_error(BOOTSTAGE_ID_POST_FAIL_R);
 			}
 		}
 	}
@@ -295,7 +295,7 @@
 		} else {
 			if ((*test->test)(flags) != 0) {
 				post_log("FAILED\n");
-				show_boot_error(BOOTSTAGE_ID_POST_FAIL_R);
+				bootstage_error(BOOTSTAGE_ID_POST_FAIL_R);
 				show_post_progress(i, POST_AFTER, POST_FAILED);
 				if (test_flags & POST_CRITICAL)
 					gd->flags |= GD_FLG_POSTFAIL;