Fix compiler warnings on 32-bit platforms.
Fix compiler warnings on 32-bit platforms.

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