Fix runit RPM file location for Chef provisionless Centos 5.9 Box Image

I just started learning Chef and was using the memcached cookbook which depends on runit. I set up my box as per https://learnchef.opscode.com/quickstart/converge/ except I provisioned using their 'opscode_centos-5.9' official box image instead.

Upon knife bootstrap, I received the error message "error: open of /root/rpmbuild/RPMS/runit-2.1.1.rpm failed: No such file or directory"

This patch resolves the issue and allows runit to install. I have confirmed memcached via runit works now on Centos 5.9.