(compare_runes): Modify for `struct rune'.

(compare_runes): Modify for `struct rune'.
(redisplay_output_layout): Use <Charc_dynarr *> instead of
<Emchar_dynarr *> for buf; use
`convert_bufbyte_string_into_charc_dynarr' instead of
`convert_bufbyte_string_into_emchar_dynarr'.