OTHER: Add missing xmmsv_ref()
OTHER: Add missing xmmsv_ref()

Could lead to double free in some cases without it.

six600110/xmms2,chrippa/xmms2,six600110/xmms2,six600110/xmms2,chrippa/xmms2,chrippa/xmms2,chrippa/xmms2,krad-radio/xmms2-krad,krad-radio/xmms2-krad,theeternalsw0rd/xmms2,theeternalsw0rd/xmms2,krad-radio/xmms2-krad,six600110/xmms2,theeternalsw0rd/xmms2,six600110/xmms2,theeternalsw0rd/xmms2,krad-radio/xmms2-krad,chrippa/xmms2,theeternalsw0rd/xmms2,six600110/xmms2,chrippa/xmms2,krad-radio/xmms2-krad,theeternalsw0rd/xmms2,krad-radio/xmms2-krad