fix memory allocation problem : vertex size is 3 floats...
fix memory allocation problem : vertex size is 3 floats...

takahito-tejima/OpenSubdiv-exp,takahito-tejima/OpenSubdiv-exp,jcowles/OpenSubdiv,shengfuintel/OpenSubdiv,takahito-tejima/OpenSubdiv,poljere/OpenSubdiv,poljere/OpenSubdiv,lookup1980/OpenSubdiv,takahito-tejima/OpenSubdiv-exp,xldeveloper/OpenSubdiv,nyotis/OpenSubdiv,takahito-tejima/OpenSubdiv,nyotis/OpenSubdiv,c64kernal/OpenSubdiv,jcowles/OpenSubdiv,nyotis/OpenSubdiv,takahito-tejima/OpenSubdiv,lookup1980/OpenSubdiv,lookup1980/OpenSubdiv,xldeveloper/OpenSubdiv,takahito-tejima/OpenSubdiv-exp,anshuarya/OpenSubdiv,shengfuintel/OpenSubdiv,shengfuintel/OpenSubdiv,poljere/OpenSubdiv,xldeveloper/OpenSubdiv,jcowles/OpenSubdiv,anshuarya/OpenSubdiv,c64kernal/OpenSubdiv,c64kernal/OpenSubdiv,anshuarya/OpenSubdiv