edeploy: Fixing RET comparaison
edeploy: Fixing RET comparaison

If no 'pre' got executed, the RET value isn't defined and led to a bash
error.

redhat-cip/edeploy,redhat-cip/edeploy,enovance/edeploy,lebauce/edeploy,enovance/edeploy,lebauce/edeploy,redhat-cip/edeploy,enovance/edeploy,redhat-cip/edeploy,lebauce/edeploy,lebauce/edeploy,enovance/edeploy