vl_printsize: improve comment
vl_printsize: improve comment

vlfeat/vlfeat,mylxiaoyi/vlfeat,j-bo/vlfeat,CansenJIANG/vlfeat,hongzhili/vlfeat,hongzhili/vlfeat,hongzhili/vlfeat,j-bo/vlfeat,CansenJIANG/vlfeat,qubick/vlfeat,erexhepa/vlfeat,vlfeat/vlfeat,j-bo/vlfeat,mylxiaoyi/vlfeat,erexhepa/vlfeat,CansenJIANG/vlfeat,hongzhili/vlfeat,richarddzh/vlfeat,vlfeat/vlfeat,richarddzh/vlfeat,CansenJIANG/vlfeat,hongzhili/vlfeat,cvfish/vlfeat,WangDequan/vlfeat,cvfish/vlfeat,qubick/vlfeat,hongzhili/vlfeat,erexhepa/vlfeat,WangDequan/vlfeat,CansenJIANG/vlfeat,qubick/vlfeat,erexhepa/vlfeat,rxl194/vlfeat,rxl194/vlfeat,erexhepa/vlfeat,WangDequan/vlfeat,mylxiaoyi/vlfeat,richarddzh/vlfeat,j-bo/vlfeat,richarddzh/vlfeat,cvfish/vlfeat,cvfish/vlfeat,vlfeat/vlfeat,rxl194/vlfeat,mylxiaoyi/vlfeat,qubick/vlfeat,j-bo/vlfeat,rxl194/vlfeat,rxl194/vlfeat,cvfish/vlfeat,rxl194/vlfeat,mylxiaoyi/vlfeat,vlfeat/vlfeat,WangDequan/vlfeat,qubick/vlfeat,erexhepa/vlfeat,WangDequan/vlfeat,richarddzh/vlfeat,richarddzh/vlfeat,mylxiaoyi/vlfeat,qubick/vlfeat,cvfish/vlfeat,CansenJIANG/vlfeat,vlfeat/vlfeat,WangDequan/vlfeat