Low: libpe_status, tools: Show container node in GuestOnline in crm_mon

Currently, the GuestOnline line shows
"<guest node>@<connection's node>". It should show "<guest node>" when
--show-detail is not set, and "<guest node>@<container's node>" when
--show-detail is set.

Here, we make the output show "<guest node>@<container's node>"
irrespective of whether --show-detail is set. We'll take care of the
--show-detail part in a future commit.

Ref T180
Ref CLBZ#5373

Signed-off-by: Reid Wahl <nrwahl@protonmail.com>