Simplify TRT build by adding onnx_tensorrt targets in CMake

[Kh4L]

Description

Add a script to build the dependencies required by MXNet-TRT: ONNX and onnx_tensorrt.

Ported from https://github.com/apache/incubator-mxnet/pull/19742

[mxnet-bot]

Hey @Kh4L , Thanks for submitting the PR All tests are already queued to run once. If tests fail, you can trigger one or more tests again with the following commands:

• To trigger all jobs: @mxnet-bot run ci [all]
• To trigger specific jobs: @mxnet-bot run ci [job1, job2]

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CI supported jobs: [windows-gpu, sanity, unix-gpu, centos-cpu, centos-gpu, edge, website, unix-cpu, windows-cpu, miscellaneous, clang]

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Note: Only following 3 categories can trigger CI :PR Author, MXNet Committer, Jenkins Admin. All CI tests must pass before the PR can be merged.

[leezu]

@mxnet-bot run ci [unix-gpu, windows-gpu]

[mxnet-bot]

Jenkins CI successfully triggered : [windows-gpu, unix-gpu]

[Kh4L]

@mxnet-bot run ci [windows-gpu]

[mxnet-bot]

Jenkins CI successfully triggered : [windows-gpu]

[leezu]

@mxnet-bot run ci [windows-gpu]

[mxnet-bot]

Jenkins CI successfully triggered : [windows-gpu]