New issue by ktm5j on void-packages repository

https://github.com/void-linux/void-packages/issues/14721

Description:
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### System

* xuname:  Void 5.2.15_1 x86_64-musl GenuineIntel uptodate rF
  *output of ``xuname`` (part of xtools)*
* package:  libvirt - 5.7.0-r0 (assuming all versions?
  *affected package(s) including the version*

### Expected behavior
After installing libvirt and configuring services, I should be able to connect to the host using virt-manager/virsh/etc and use normally

### Actual behavior
libvirt starts properly, and I can connect using virt-manager/virsh.. however once I try to create a VM I am given this error message:

```
[root@ruby ~ ]# virsh create /tmp/vm.xml
error: Failed to create domain from /tmp/vm.xml
error: internal error: child reported (status=125): Unable to get host boot time: No data available  
```

### Steps to reproduce the behavior

Install libvirt under musl and try using it

I have tracked the error down to an issue with musl's lack of utmpx implementation.  The error message is generated by [this if statement in libvirt](https://github.com/libvirt/libvirt/blob/3ebde403c76ee046c53ebf7b80dff7eb11e94748/src/security/security_util.c#L117) 

The function is calling [virHostGetBootTime() from src/util/virhostuptime.c](https://github.com/libvirt/libvirt/blob/3ebde403c76ee046c53ebf7b80dff7eb11e94748/src/util/virhostuptime.c#L36) where the error occurs.  This function is calling `getutxid()` from `utmpx.h` however the musl implementation of utmpx simply returns NULL for this and many other functions.

Has libvirt ever worked under musl?  Is this happening now because of a change that was made in libvirt?  Sorry if this is the wrong place to file this issue, but I would really like to get this working if possible

Thanks