AM625: Patch OS generated by buildroot

Depends really on the scope of the patches I would say. Usually in real-world deployments you often update the entire FW image, using some kind of A/B scheme for robustness sake. This will make sure all systems in the field have a certain known-good baseline. Also, Buildroot itself is rather simplistic and really intended to build software for a fixed system and with that doesn't lend itself well to incremental updates. If you want to incrementally update SW packages you should consider Yocto, or even Debian, which all come with package management infrastructure and tooling.

Regards, Andreas