(make_byte_table): Add new argument `older'.

(make_byte_table): Add new argument `older'.
(make_char_id_table): Likewise.
(copy_char_id_table): Comment out because it is not used.
(put_char_id_table): Modify for `make_byte_table'.
(Fput_char_attribute): Make encoding_table as older object; inherit
older bit of `Vcharacter_composition_table'.
(mark_charset): Don't mark `cs->encoding_table'.
(vars_of_mule_charset): Make `Vcharacter_attribute_table' as a normal
object; make `Vcharacter_composition_table' as an older object; delete
staticpro for `Vcharacter_composition_table'; make
`Vcharacter_variant_table' as a normal object.