Export FireRedASR to ONNX

[csukuangfj]

See also https://github.com/FireRedTeam/FireRedASR
and
https://huggingface.co/FireRedTeam/FireRedASR-AED-L/tree/main

Note it supports both Chinese and English.

The Large version is quite large. See the exported onnx model files below:

total 1.7G
-rw-r--r-- 1 runner docker  188 Feb 16 08:46 README.md
-rw-r--r-- 1 runner docker 425M Feb 16 08:45 decoder.int8.onnx
-rw-r--r-- 1 runner docker 1.3G Feb 16 08:46 encoder.int8.onnx
drwxr-xr-x 2 runner docker 4.0K Feb 16 08:45 test_wavs
-rw-r--r-- 1 runner docker  70K Feb 16 08:46 tokens.txt

You can download it from
https://github.com/k2-fsa/sherpa-onnx/releases/tag/asr-models

We will open-source the export code once the xs version of the model from
https://github.com/FireRedTeam/FireRedASR
is open-sourced.