Added support for Jetson Orin Nano with JETSON_L4T=35.4.1 and JETSON_JETPACK=5.1.2

[manavjeetsingh]

Description

• Added support for Jetson Orin Nano with JETSON_L4T=35.4.1 and JETSON_JETPACK=5.1.2.
• Fixed a bug in scripts/getKernelSources.sh:81 which was unable to recognize and throw error if SOURCE_URL is empty.
• Updated readme.md and added Jetson Orin NX and Jetson Orin Nano in supported devices.

Checklist:

• My pull request has a descriptive title (not a vague title like Update index.md).
• My pull request targets the master branch of the repository.
• My commit messages follow best practices.
• I added tests for the changes I made (if applicable).
• I added or updated documentation (if applicable).
• I tried running the project locally and verified that there are no
  visible errors.

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