Remove 'ceph-deploy osd activate'

Remove Exec['ceph-deploy osd activate'] because the same
is done by Service['ceph'], that is more preferable.

Change-Id: I47cae0a4f937be565238818b597811f936ca493a
Closes-Bug: 1374160
Merge "Remove 'ceph-deploy osd activate'" into stable/5.1