vzctl --help: fix convert synopsys

Remove --diskspace option.

The story is there was an idea to add it, but then it was decided
that it's easier just to use vzctl set --diskspace right before
vzctl convert.

https://bugzilla.openvz.org/2809

Reported-by: Pavel Odintsov <pavel.odintsov@gmail.com>
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
1 file changed