When trying to execute ALTER TABLE EXCHANGE PARTITION with different
definitions, assertion
table->s->db_create_options == part_table->s->db_create_options
failed in compare_table_with_partition().
However, this execution should not be allowed since executing
'exchange partition' requires the identical structure of the two tables.
To fix the problem, I deleted the assertion code and added code that
returns an error that indicates tables have different definitions.
Reviewed By: Nayuta Yanagisawa
