Description of problem:
- When using host with AMD architecture and setting VM OS to windows 10/windows 10 x64, the action rejected with "The guest OS doesn't support the following CPUs: opteron_g4, opteron_g3, opteron_g5, opteron_g2, opteron_g1, penryn, nehalem, conroe. Its possible to change the cluster cpu or set a different one per VM".
- It is possible to run same VM when using "other" OS type.
- Same action using Intel host is not rejected by the webadmin.

Version-Release number of selected component (if applicable):
rhevm-3.5.6.1-0.1.el6ev (vt18).
qemu-kvm-rhev-2.1.2-23.el7_1.10.x86_64
libvirt-client-1.2.8-16.el7_1.4.x86_64
vdsm-4.16.28-1.el7ev.x86_64
sanlock-3.2.2-2.el7.x86_64

How reproducible:
100%

Steps to Reproduce:
1. Create windows 10 VM.
2. Edit VM > from operating system dropbox, select windows 10.
3. Click OK.

Actual results:
Action rejected with error message: 
he guest OS doesn't support the following CPUs: opteron_g4, opteron_g3...
engine log:
2015-11-05 15:52:45,866 INFO  [org.ovirt.engine.core.bll.UpdateVmCommand] (ajp-/127.0.0.1:8702-11) [29ec214b] Lock Acquired to object EngineLock [exclusiveLocks= key: win10 value: VM_NAME
, sharedLocks= key: 4c7ee3c3-3d5c-4c89-b129-1599e930afc9 value: VM
]
2015-11-05 15:52:45,868 WARN  [org.ovirt.engine.core.bll.UpdateVmCommand] (ajp-/127.0.0.1:8702-11) [29ec214b] CanDoAction of action UpdateVm failed for user admin@internal. Reasons: VAR__ACTION__UPDATE,VAR__TYPE__VM,CPU_TYPE_UNSUPPORTED_FOR_THE_GUEST_OS,$unsupportedCpus opteron_g4, opteron_g3, opteron_g5, opteron_g2, opteron_g1, penryn, nehalem, conroe
2015-11-05 15:52:45,869 INFO  [org.ovirt.engine.core.bll.UpdateVmCommand] (ajp-/127.0.0.1:8702-11) [29ec214b] Lock freed to object EngineLock [exclusiveLocks= key: win10 value: VM_NAME
, sharedLocks= key: 4c7ee3c3-3d5c-4c89-b129-1599e930afc9 value: VM
]

Expected results:
Windows 10 OS type should be set on VM without exceptions.

Additional info:
Severity set to high because guest agent cannot be run on windows 10 VM when using AMD architecture.
vdsm, VM XML and engine logs attached.