- Update rtems-bsp support to correctly handle hosts for BSP.
- Clean up the options for a BSP.
- Check all RTEMS 5 packages and add 5/rtems-packages for all that build.
- Update download locations and checksum of all packages.
- The work requires the kernel and Libbsd hacve the same prefix.
The support is added at the top level and so not lost when we
move to a new version of RTEMS.
The change also moves all 3rd party packages to use a common
rtems-package.bset build set file.
All packages except Microwindows itself build cleanly.
