[SPARK-7026] [SQL] fix left semi join with equi key and non-equi condition

When the `condition` extracted by `ExtractEquiJoinKeys` contain join Predicate for left semi join, we can not plan it as semiJoin. Such as

    SELECT * FROM testData2 x
    LEFT SEMI JOIN testData2 y
    ON x.b = y.b
    AND x.a >= y.a + 2
Condition `x.a >= y.a + 2` can not evaluate on table `x`, so it throw errors

Author: Daoyuan Wang <daoyuan.wang@intel.com>

Closes #5643 from adrian-wang/spark7026 and squashes the following commits:

cc09809 [Daoyuan Wang] refactor semijoin and add plan test
575a7c8 [Daoyuan Wang] fix notserializable
27841de [Daoyuan Wang] fix rebase
10bf124 [Daoyuan Wang] fix style
72baa02 [Daoyuan Wang] fix style
8e0afca [Daoyuan Wang] merge commits for rebase