Description of problem:
There is no ability to configure 'DefaultMtu' config value via engine-config tool.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. ~/ovirt-engine/bin/engine-config -s "DefaultMtu=150"
"Error setting DefaultMtu's value. No such entry."
'DefaultMtu' value is updated to 80 in vdc_options table.
oVirt 3.5 has been released and should include the fix for this issue.