Description of problem:
[SR-IOV] - Edit vNIC profile > 'QoS' should be disabled if 'passthrough' is checked and used by VM.

- On new vNIC profile dialog, QoS and Port mirroring are disabled when checking 'passthrough' check box , the same should be for the edit vNIC profile dialog if 'passthrough' is checked and the profile is used by VM. 
Today on the edit vNIC profile dialog the 'QoS' is not cleaned and the 'QoS' is editable and can be updated.

Version-Release number of selected component (if applicable):
3.6.0-0.12.master.el6

How reproducible:
100

Steps to Reproduce:
1. Create network with 'passthrough' profile(QoS and Port mirroring are disabled) and add to VM
2. Create QoS(VM network) via DC
3. Edit vNIC profile with network QoS

Actual results:
It is possible to update vNICs profile with network QoS when 'passthrough' is checked and profile is used by VM. QoS is not cleaned when 'passthrough' is checked in the edit dialog.

Expected results:
QoS should be disabled on the edit vNIC profile dialog if 'passthrouhg' is checked and used by VM