test: boot: Update bootflow_iter() for console checking

This test checks console output so should have the UTF_CONSOLE flag. Add
it.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/test/boot/bootflow.c b/test/boot/bootflow.c
index 8762d21..2f859c4 100644
--- a/test/boot/bootflow.c
+++ b/test/boot/bootflow.c
@@ -370,7 +370,7 @@
 
 	return 0;
 }
-BOOTSTD_TEST(bootflow_iter, UTF_DM | UTF_SCAN_FDT);
+BOOTSTD_TEST(bootflow_iter, UTF_DM | UTF_SCAN_FDT | UTF_CONSOLE);
 
 #if defined(CONFIG_SANDBOX) && defined(CONFIG_BOOTMETH_GLOBAL)
 /* Check using the system bootdev */