pc-dimm: Drop @errp argument of pc_dimm_plug()

pc-dimm: Drop @errp argument of pc_dimm_plug()

pc_dimm_plug() doesn't use it. It only aborts on error.

Drop @errp and adapt the callers accordingly.

[dwg: Removed unused label to fix compile]
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <160309728447.2739814.12831204841251148202.stgit@bahia.lan>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>