Fix path of install_dir of 32bit CentOS
Fix path of install_dir of 32bit CentOS

GoogleCloudPlatform/google-fluentd,treasure-data/omnibus-td-agent,GoogleCloudPlatform/google-fluentd,treasure-data/omnibus-td-agent,treasure-data/omnibus-td-agent,iantalarico/google-fluentd,iantalarico/google-fluentd,GoogleCloudPlatform/google-fluentd,iantalarico/google-fluentd