Create `Range columns` type partition error

[ciscoxll]

Please answer these questions before submitting your issue. Thanks!

1. What did you do?

create table t29 (
    a decimal
)  partition by range columns (a)(
    partition p0 values less than (0)
);

2. What did you expect to see?

Meet no error.

3. What did you see instead?

ERROR HY000: Field 'a' is of a not allowed type for this type of partitioning

The range partition comes in two varieties:

• a. partition by range(expr) support
• b. partition by range columns(column_list) not support

Range columns partition only implements the parser, so it will not be checked. So the DDL should run successfully.

4. What version of TiDB are you using (tidb-server -V or run select tidb_version(); on TiDB)?

master branch 129f499