[marif-nexthop]

Pre-submission checklist

• I've ran the linters locally and fixed lint errors related to the files I modified in this PR. You can install the linters by running pip install -r requirements-dev.txt && pre-commit install
• pre-commit run

Summary

PR commit stack:

1. [Nexthop][m4340nhp] Add the platform mapping #1876
2. This (top of stack)

• Add the Qumran4D ASIC data and register it with the DNX generator.
• Add the m4340nhp asic_config.json and the SDK configs generated from it for the default and hw_test variants.

Test Plan

gen.py --platform m4340nhp writes both generated configs, and validate_asic_configs_schemas passes. validate_asic_configs_contents reports REFERENCE_MISSING for both m4340nhp variants, because no reference config exists for them yet.