HFileWriter, HFileReader and HFileDataBlock should avoid hardcoded key field name

Today HFileReader has the hardcoded key field name for the schema. This key field is used by HFileWriter, HFileDataBlock for HFile key dedupliacation feature. When users want to use the HFile format, this hard coded key field name can be preventing the usecase. We need a way to pass in the writer/reader/query configs to the HFile storage layer so as to use the right key field name. 

Related: HUDI-2763

## JIRA info

- Link: https://issues.apache.org/jira/browse/HUDI-3321
- Type: Improvement
- Epic: https://issues.apache.org/jira/browse/HUDI-6243
- Fix version(s):
- 1.1.0

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## Comments

30/Mar/22 06:15;xushiyan;Discussed with [~shivnarayan] we need this when we want to support hfile as base file. cc [~guoyihua]
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