[DAP/Whisper]Add initial documents for Whisper Preprocessor.

[taiqzheng]

Currently, it is in draft form with some remaining work to be completed.
However, it is now capable of being used to build an end-to-end Whisper model.

Work should be done in this PR:

• Correct format for data
  Theclang-formattool offers different strategies for formatting data. Please check file ExtandDAPPass.cpp in “Files changed”.
• Add an example
  The example has been designed, but the file location needs to be changed.
• Correct the relationship with DAP Pass
  Update file locations for the extand-dap pass and also change the operation name.

Future work, not in this PR:

• Update pass pipeline
  The one-shot-bufferize pass has conflicts with some operations.
• Update example
  Currently only one case is supported, where its audio data is directly written into the example file. To support more audio cases, we need an audio library to read data from audio files.
• Extract operators
  Some operators need to be extracted so that they can be reused in other algorithms.
• Optimize the algorithm
  After extracting the operators, design vectorization pattern for each one.

[zhanghb97]

Thanks!