## What changes were proposed in this pull request?
With https://github.com/apache/spark/pull/21389, data source schema is validated on driver side before launching read/write tasks.
However,
1. Putting all the validations together in `DataSourceUtils` is tricky and hard to maintain. On second thought after review, I find that the `OrcFileFormat` in hive package is not matched, so that its validation wrong.
2. `DataSourceUtils.verifyWriteSchema` and `DataSourceUtils.verifyReadSchema` is not supposed to be called in every file format. We can move them to some upper entry.
So, I propose we can add a new method `validateDataType` in FileFormat. File format implementation can override the method to specify its supported/non-supported data types.
Although we should focus on data source V2 API, `FileFormat` should remain workable for some time. Adding this new method should be helpful.
## How was this patch tested?
Unit test
Author: Gengliang Wang <gengliang.wang@databricks.com>
Closes#21667 from gengliangwang/refactorSchemaValidate.
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