corrected typo in frontend/QF_BV.hpp
corrected typo in frontend/QF_BV.hpp

finnhaedicke/metaSMT,hoangmle/metaSMT,finnhaedicke/metaSMT,nbruns1/metaSMT,agra-uni-bremen/metaSMT,agra-uni-bremen/metaSMT,nbruns1/metaSMT,hoangmle/metaSMT,agra-uni-bremen/metaSMT,nbruns1/metaSMT,finnhaedicke/metaSMT,hoangmle/metaSMT