ess reader: use _fileno for win32 and _fseeki64 for msvc
ess reader: use _fileno for win32 and _fseeki64 for msvc

kierank/bmxlib-bmx,xunchangguo/BMX,kierank/bmxlib-bmx,ebu/ebu-bmx,Limecraft/ebu-bmx,kierank/bmxlib-bmx,ebu/ebu-bmx,Limecraft/ebu-bmx,stuarthicks/bmx,Limecraft/ebu-bmx,stuarthicks/bmx,stuarthicks/bmx,ebu/ebu-bmx,xunchangguo/BMX,xunchangguo/BMX