Modeline cleanup

If users want folds to be automatically collapsed, then they should just
set foldmethod=marker in their vimrc.

src/nvim/ex_cmds.c

@@ -6316,5 +6316,3 @@ void set_context_in_sign_cmd(expand_T *xp, char_u *arg)
     }
   }
 }
-
-// vim: tabstop=8

src/nvim/terminal.c

@@ -1126,4 +1126,4 @@ static int get_config_int(Terminal *term, char *key)
 
 // }}}
 
-// vim: foldmethod=marker foldenable
+// vim: foldmethod=marker