Description of problem:
virtiofsd reports a warning when options compatible with the C implementation are used:

1. cat /var/log/libvirt/qemu/test2-ua-8d50d10c-719d-11ed-91f4-3a40aa736603-virtiofsd.log
   [2023-02-20T02:22:45Z WARN virtiofsd] Use of deprecated option format 'o': Please specify options without it (e.g., '-cache auto' instead of '-o cache=auto')
   [2023-02-20T02:22:45Z INFO virtiofsd] Waiting for vhost-user socket connection...

2.Check the virtiofsd usage:
#/usr/libexec/virtiofsd --help
..
OPTIONS:
--cache <cache>
The caching policy the file system should use (auto, always, never) [default: auto]

-o <compat-options>...
Options in a format compatible with the legacy implementation
**[deprecated]**

However, the vhost-user interoperability file still remains identical to the one provided by the C version:
{
"description": "QEMU virtiofsd vhost-user-fs",
"type": "fs",
"binary": "/usr/libexec/virtiofsd"
}

Some sort of hint/flag/capability to let libvirt know it's dealing with an incompatible implementation would be helpful.

Version-Release number of selected component (if applicable):
virtiofsd-1.5.0-1.el9.x86_64