patch 8.2.5109: mode not updated after CTRL-O CTRL-C in Insert mode

Problem:    Mode not updated after CTRL-O CTRL-C in Insert mode.
Solution:   Set redraw_mode and use it. (closes #10581)
diff --git a/src/main.c b/src/main.c
index 3d86796..2ffee14 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1419,7 +1419,7 @@
 		update_screen(0);
 		mch_enable_flush();
 	    }
-	    else if (redraw_cmdline || clear_cmdline)
+	    else if (redraw_cmdline || clear_cmdline || redraw_mode)
 		showmode();
 	    redraw_statuslines();
 	    if (need_maketitle)