terminal/screen: mark cursor dirty on enabled/disable

If we hide or show the cursor, we change visual attributes and have to
mark the underlying cell as dirty. Otherwise, the terminal will not be
redrawn.

src/libsystemd-terminal/term-screen.c

@@ -419,6 +419,7 @@ static void screen_mode_change(term_screen *screen, unsigned int mode, bool dec,
                          * TODO
                          */
                         set_reset(screen, TERM_FLAG_HIDE_CURSOR, !set);
+                        screen_age_cursor(screen);
                 }
 
                 break;