toulon beat wasps in their european rugby champions cup quarter-final .
toulon and wasps scored two tries each at the felix mayol stadium .
no 10 frederic michalak kicked six penalties and two conversions .
william helu scored two tries for the visitors in a gallant effort .
they face leinster for a place in the european champions cup final .
saracens earlier defeated racing metro 92 by 12-11 in a thriller .