Don't map xenserver to RHEL 5
Don't map xenserver to RHEL 5

Each xenservers major release is mapped to a major release of RHEL.
They're on 7.X now. This means xenserver users can install Chef 14 now
since we don't have a RHEL 5 build of Chef anymore

Signed-off-by: Tim Smith <764ef62106582a09ed09dfa0b6bff7c05fd7d1e4@chef.io>

chef/omnitruck,chef/omnitruck,chef/omnitruck,chef/opscode-omnitruck,chef/opscode-omnitruck,chef/opscode-omnitruck