Description of problem:
"cpu-baseline"  command doesn't deal with "cmt" feature 
and fail to start a domain which cpu part is generated by "cpu-baseline" .

Version-Release number of selected component (if applicable):
libvirt-3.2.0-4.el7.x86_64
qemu-kvm-rhev-2.9.0-3.el7.x86_64


How reproducible:

100%
Steps to Reproduce:

1. There are two cpu models and get the cpu part from "virsh capabilities"  to cpu.xml as below:
<cpu>
      <arch>x86_64</arch>
      <model>Broadwell</model>
      <vendor>Intel</vendor>
      <topology sockets='1' cores='8' threads='2'/>
      <feature name='vme'/>
      <feature name='ds'/>
      <feature name='acpi'/>
      <feature name='ss'/>
      <feature name='ht'/>
      <feature name='tm'/>
      <feature name='pbe'/>
      <feature name='dtes64'/>
      <feature name='monitor'/>
      <feature name='ds_cpl'/>
      <feature name='vmx'/>
      <feature name='smx'/>
      <feature name='est'/>
      <feature name='tm2'/>
      <feature name='xtpr'/>
      <feature name='pdcm'/>
      <feature name='dca'/>
      <feature name='osxsave'/>
      <feature name='f16c'/>
      <feature name='rdrand'/>
      <feature name='arat'/>
      <feature name='tsc_adjust'/>
      <feature name='cmt'/>
      <feature name='xsaveopt'/>
      <feature name='mbm_total'/>
      <feature name='mbm_local'/>
      <feature name='pdpe1gb'/>
      <feature name='abm'/>
      <feature name='invtsc'/>
      <pages unit='KiB' size='4'/>
      <pages unit='KiB' size='2048'/>
      <pages unit='KiB' size='1048576'/>
    </cpu>


<cpu>
      <arch>x86_64</arch>
      <model>Haswell-noTSX</model>
      <vendor>Intel</vendor>
      <topology sockets='1' cores='18' threads='2'/>
      <feature name='vme'/>
      <feature name='ds'/>
      <feature name='acpi'/>
      <feature name='ss'/>
      <feature name='ht'/>
      <feature name='tm'/>
      <feature name='pbe'/>
      <feature name='dtes64'/>
      <feature name='monitor'/>
      <feature name='ds_cpl'/>
      <feature name='vmx'/>
      <feature name='smx'/>
      <feature name='est'/>
      <feature name='tm2'/>
      <feature name='xtpr'/>
      <feature name='pdcm'/>
      <feature name='dca'/>
      <feature name='osxsave'/>
      <feature name='f16c'/>
      <feature name='rdrand'/>
      <feature name='arat'/>
      <feature name='tsc_adjust'/>
      <feature name='cmt'/>
      <feature name='xsaveopt'/>
      <feature name='pdpe1gb'/>
      <feature name='abm'/>
      <feature name='invtsc'/>
      <pages unit='KiB' size='4'/>
      <pages unit='KiB' size='2048'/>
      <pages unit='KiB' size='1048576'/>
    </cpu>

2. Use "Virsh cpu-baseline" command to get the baseline CPU part.
# virsh cpu-baseline cpu.xml
<cpu mode='custom' match='exact'>
  <model fallback='allow'>Haswell-noTSX</model>
  <vendor>Intel</vendor>
  <feature policy='require' name='vme'/>
  <feature policy='require' name='ds'/>
  <feature policy='require' name='acpi'/>
  <feature policy='require' name='ss'/>
  <feature policy='require' name='ht'/>
  <feature policy='require' name='tm'/>
  <feature policy='require' name='pbe'/>
  <feature policy='require' name='dtes64'/>
  <feature policy='require' name='monitor'/>
  <feature policy='require' name='ds_cpl'/>
  <feature policy='require' name='vmx'/>
  <feature policy='require' name='smx'/>
  <feature policy='require' name='est'/>
  <feature policy='require' name='tm2'/>
  <feature policy='require' name='xtpr'/>
  <feature policy='require' name='pdcm'/>
  <feature policy='require' name='dca'/>
  <feature policy='require' name='osxsave'/>
  <feature policy='require' name='f16c'/>
  <feature policy='require' name='rdrand'/>
  <feature policy='require' name='arat'/>
  <feature policy='require' name='tsc_adjust'/>
  <feature policy='require' name='cmt'/>
  <feature policy='require' name='xsaveopt'/>
  <feature policy='require' name='pdpe1gb'/>
  <feature policy='require' name='abm'/>
  <feature policy='require' name='invtsc'/>
</cpu>

3. 
Tried to use above part in the machine with Haswell-noTSX CPU model and the guest failed to start for below error:

[root@intel-brickland-04 images]# virsh start rhel7_1
error: Failed to start domain rhel7_1
error: internal error: process exited while connecting to monitor: 2017-05-12T08:07:53.701712Z qemu-kvm: -chardev pty,id=charserial0: char device redirected to /dev/pts/1 (label charserial0)
2017-05-12T08:07:53.706843Z qemu-kvm: can't apply global Haswell-noTSX-x86_64-cpu.cmt=on: Property '.cmt' not found

Actual results:
As in step3, fail to start a domain which cpu part is generated by "cpu-baseline"

Expected results:

Should succeed to start a domain which cpu part is generated by "cpu-baseline"

Additional info: