fix otool being called on linux [skip appveyor]
fix otool being called on linux [skip appveyor]

JCMais/node-libcurl,JCMais/node-libcurl,JCMais/node-libcurl,JCMais/node-libcurl,JCMais/node-libcurl,JCMais/node-libcurl,JCMais/node-libcurl