ass_parse: remove 2 unused variables
ass_parse: remove 2 unused variables

Fallout from the previous commits.

astiob/libass,torque/libass,libass/libass,xbmc/libass,xbmc/libass,sanyaade-g2g-repos/libass,ShiftMediaProject/libass,stps/libass,ShiftMediaProject/libass,Akemi/libass,sanyaade-g2g-repos/libass,astiob/libass,Akemi/libass,mwgoldsmith/libass,stps/libass,torque/libass,MrSmile/libass,MrSmile/libass,sanyaade-g2g-repos/libass,Akemi/libass,grigorig/libass,libass/libass,mwgoldsmith/libass,torque/libass,grigorig/libass,mwgoldsmith/libass,pigoz/libass-ct,pigoz/libass-ct,pigoz/libass-ct,stps/libass