core/driver: Add version information

core/driver: Add version information

Create a version string in the format

    vX.Y (<commits-since-vX.Y>-<git-hash>[-dirty])

and embed it into the hypervisor core as well as the driver module.
Helps to identify what is actually executed.

The management tool is more decoupled from those two and will get a
simpler version tag.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>