updated for version 7.4.288

Problem:    When 'spellfile' is set the screen is not redrawn.
Solution:   Redraw when updating the spelling info. (Christian Brabandt)

src/spell.c

@@ -4508,6 +4508,7 @@ did_set_spelllang(wp)
 theend:
     vim_free(spl_copy);
     recursive = FALSE;
+    redraw_win_later(wp, NOT_VALID);
     return ret_msg;
 }