west: runners: nrf: Add support for the suit manifest starter

With the recent introduction of the SUIT manifest starter binary blob,
it is now possible to use it with the nRF54H20 during the flashing
procedure in order to provide a valid SUIT manifest to the system.

This PR introduces the code that handles programming the SUIT manifest
starter, as well as a new --suit-manifest-starter command-line option.

Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>