Following the reasons to choose LGPL 2.0 or later:
* the work is done by CERN, so a public organization. Anyone should benefit
  from CERN work without too many restricions.
* The project contains also kernel code and in order to be submittable to
  the Linux kernel the project must be a GPL 2.0 or compatible.

Signed-off-by: Federico Vaga <federico.vaga@cern.ch>