Bug 2077328

### Description of problem:
When we dump a definition of a VM that was created on Openstack, 
it looks like the xml contains improperly a new line character.

A same issue was reported in libvirt bug and already fixed:

Fixed bug: 
https://github.com/libvirt/libvirt/commit/b29c86ae1042fc44e7c86f3519f048a696e68afe

Related bug:
https://bugzilla.redhat.com/show_bug.cgi?id=2032795

This bug had fixed on libvirt-client 7.0.1 later. However, this issue has occurred in RHOSP16.2.  And RHOSP16.2 depends on RHEL8.4. Please backport the fix to libvit-client on RHEL8.4.

### Version-Release number of selected component (if applicable):

libvirt-client-6.0.0-35.1.module+el8.4.0+11273+64eb94ef.x86_64 Mon Apr 18 15:57:53 2022

### How reproducible:

Anytime

### Steps to Reproduce:

Run virsh dumpxml with the VM that contains the vhostuser ifname.

### Actual results:

When we dump a definition of a VM that was created on Openstack,
it looks like the xml contains improperly a new line character.

    <interface type='vhostuser'>
      <mac address='XX:XX:XX:XX:XX:XX'/>
      <source type='unix' path='/var/lib/vhost_sockets/vhu05b874eb-f6' mode='server'/>
      <target dev='vhu05b874eb-f6       <------ here is a improperly new line character
'/>
      <model type='virtio'/>
      <driver rx_queue_size='1024' tx_queue_size='1024'/>
      <alias name='net0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </interface>

This behavior does not occur in RHOSP13.


### Expected results:
Remove extra '\n' from vhostuser ifname