Merge changes from topic "nrd1_deprecation" into integration

* changes:
  docs(changelog): remove RD-E1-Edge platform's scope
  docs(maintainers): add RD-V3 variants to maintained paths
  feat(neoverse_rd): deprecate and remove RD-V1 platform variants
  feat(neoverse_rd): deprecate and remove RD-N1-Edge platform variants
  feat(neoverse_rd): deprecate and remove SGI-575 platform