[Tracking Issue] Arm Ethos-N updates

[leo-blonk]

This issue is to track progress for planned updates for the Arm Ethos-N.

• P1. Alignment of IsSupported calls and compiler for different variants ([ETHOSN] Match config for is-supported with compilation target #9160). This paves the way for P2.
• P2. Support for variants. This allows code generation for a number of Ethos-N78 hardware configurations with default memories ([ETHOSN] Add support for non-default Ethos(TM)-N78 configurations #9386).
• P3. Remove some code duplication, fix double specification of target variant, consistent naming of target and product names, general cleanup
• P4. Support for configurable sram memories. This extends P2 above to also specify the amount of on-board memory. Update: no change required. A future update will improve the error handling when memory is specified incorrectly.

[masahi]

I assume it has been completed.