[legal] Add licence.pl and %.licence make target

It is now possible to run e.g.

  make bin/rtl8139.dsk.licence

in order to see a licensing assessment for any given gPXE build.  The
assessment will either produce a single overall licence for the build
(based on combining all the licences used within the source files for
that build), or will exit with an error stating why a licence
assessment is not possible (for example, if there are files involved
that do not yet contain an explicit FILE_LICENCE() declaration).
3 files changed
tree: 24464edc273fd4f5dab7d8d4212d3c03fca38997
  1. contrib/
  2. src/
  3. COPYING
  4. COPYRIGHTS
  5. LOG
  6. README