EITS: wrong selectivity for REF(t1.key=t0.col) AND COND(t0.col)

## Dataset from MDEV-5985:

create table ten(a int);

insert into ten values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);

create table one_k(a int);

insert into one_k select A.a + B.a* 10 + C.a * 100 from ten A, ten B, ten C;

create table one_k2 as select * from one_k;

set histogram_size=100;

set use_stat_tables='preferably';

set optimizer_use_condition_selectivity=4;

analyze table one_k persistent for all;

analyze table one_k2 persistent for all;

# Extra data for this MDEV:

create table one_k3 (a int, b int, key(a));

insert into one_k3 select A.a + 10*B.a, 12345 from ten A, ten B, ten C;

analyze table one_k3 persistent for all;

explain extended select * from one_k2 straight_join one_k3 where one_k2.a=one_k3.a and one_k2.a<10;

+------+-------------+--------+------+---------------+------+---------+--------------+------+----------+-------------+

| id   | select_type | table  | type | possible_keys | key  | key_len | ref          | rows | filtered | Extra       |

+------+-------------+--------+------+---------------+------+---------+--------------+------+----------+-------------+

|    1 | SIMPLE      | one_k2 | ALL  | NULL          | NULL | NULL    | NULL         | 1000 |     0.99 | Using where |

|    1 | SIMPLE      | one_k3 | ref  | a             | a    | 5       | j22.one_k2.a |   10 |     9.90 |             |

+------+-------------+--------+------+---------------+------+---------+--------------+------+----------+-------------+