gnu: Add ganeti.

gnu: Add ganeti.

* gnu/packages/virtualization.scm (system->qemu-target, ganeti): New variables.
* gnu/packages/patches/ganeti-deterministic-manual.patch,
gnu/packages/patches/ganeti-disable-version-symlinks.patch,
gnu/packages/patches/ganeti-drbd-compat.patch,
gnu/packages/patches/ganeti-haskell-pythondir.patch,
gnu/packages/patches/ganeti-os-disk-size.patch,
gnu/packages/patches/ganeti-preserve-PYTHONPATH.patch,
gnu/packages/patches/ganeti-shepherd-master-failover.patch,
gnu/packages/patches/ganeti-shepherd-support.patch: New files.
* gnu/local.mk (dist_patch_DATA): Adjust accordingly.