Integrate meta-guf-distro/fnginstall-yocto

Commit: https://gitlab.com/garz-fricke/yocto/layers/meta-guf-distro/-/commit/cfe1435314483c3439bb4ef54a8e5969876e60a3

fng-install: first implementation of A-B installation and new partition scheme

Use partitioning code and so on from common script. Use A-B partitions as detected. Probably not handled all cases when the partition layout differs from the expected ones.

BCS 746-000400