This directory is only required, if some local source files or other types of files are required to build the BSP's root filesystem. For this generic BSP its used to show ptxdist's binary files inclusion feature. If you derive your own BSP from this generic BSP, and you do not need such a feature, you can remove this directory and its content. You can find a description of this feature in our application note "How to become a ptxdist Guru" in chapter "Adding Binaries"