bufferfragment_p fix PVS-Studio issue V612 unconditional return in loop
Fix PVS-Studio issue "src/core/bufferfragment_p.h:88: warning: V612 An unconditional 'return' within a loop.".
Fix PVS-Studio issue "src/core/bufferfragment_p.h:88: warning: V612 An unconditional 'return' within a loop.".