The fwidgen tool duplicates a lot of the is_lpc55 function from the RawHubrisArchive type. This tool needs to differentiate between lpc55 & stm32 chips but adding an is_stm32 function didn't feel right. We'd prefer an abstraction, something like the Chips enum from the fwidgen tool that can TryFrom<RawHubrisArchive> for all supported chips. This will however change the hubtools API so we left this as future work in #38. Ideally we'd depricate the is_lpc55 function, but we could remain backward compatible by using the enum behind the scenes.