Fixed

• nRF54L key provisioning: The key length is now checked if it is a multiple of 16 bytes, as this is what the KMU expects.
• Fixed an issue where it was not possible to read the FICR content into a file on nRF54H20.
• Passing --x-append-batch along with --traits or --serial-number was meant to error out because of conflicts in the arguments, but didn't. This has now been fixed.