kernel: get_image_version()
kernel: get_image_version()

Use 'dpkg-deb -c' for debs instead of rolling our own.

Signed-off-by: Ilya Dryomov <152d4c5bebf13a5b809d42b4d789cf9d887e6698@redhat.com>

zhouyuan/teuthology,tchaikov/teuthology,SUSE/teuthology,SUSE/teuthology,caibo2014/teuthology,dmick/teuthology,michaelsevilla/teuthology,michaelsevilla/teuthology,ceph/teuthology,ktdreyer/teuthology,dmick/teuthology,tchaikov/teuthology,caibo2014/teuthology,zhouyuan/teuthology,ktdreyer/teuthology,dreamhost/teuthology,ivotron/teuthology,robbat2/teuthology,t-miyamae/teuthology,yghannam/teuthology,yghannam/teuthology,ceph/teuthology,dreamhost/teuthology,ivotron/teuthology,dmick/teuthology,t-miyamae/teuthology,SUSE/teuthology,robbat2/teuthology