Fix platform names in release.omnibus.yml
Fix platform names in release.omnibus.yml

Fix platform names in release.omnibus.yml to conform with what
the new package publishing code in the omnibus gem expects.

Signed-off-by: Jeremiah Snapp <a9df78b4b5c00745f26b0821b2cc57336a474862@chef.io>

chef/opscode-pushy-client,chef/opscode-pushy-client,chef/opscode-pushy-client