Update link to Hexagon delegate guide
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For the most up to date status, view the checks section at the bottom of the pull request. Hi @yijie-yang Can you please review this PR ? Thank you! Hi @gbaned, I'm not authorized to merge this PR. Could you request it from Hexagon team?
In TensorFlow Lite C++ image classification demo, the link to the Hexagon delegate guide is outdated. This PR updates it to the correct one.