ceph: fix apt-key for ceph
common: Don't be verbose is ret=0

If ret=0, that's a normal exit case, there is no need to print debbuging
messages.
test target depends on mysql.done

The dependency is defined in kvm-test.configure:

    set_role('mysql', 'D7-F.1.0.0', disk1)
doc: list required packages on Debian