tflite: Decompose model with multiple indices

Previously, we could only decompose tflite model as a single-op model.
This can't help if a specific subset of operators is required.
Therefore, the decomposing with multiple indices is introduced.

BUG=b:353609613, b:331900692
TEST=bazel run --config=host_clang common:decompose_model -- decompose
     --input=<input> --output=<output> --op_index=<multiple indices>
     # using `decompose_model list` to see the result.

Change-Id: Ibd159634c15be9fef2203a40469d67b337a47021
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/tflite/+/5723752
Commit-Queue: Ching-Kang Yen <chingkang@chromium.org>
Reviewed-by: Shik Chen <shik@chromium.org>
Tested-by: Ching-Kang Yen <chingkang@chromium.org>