[Virtio-fs] [virtiofsd] MR closed: fuse: Debug-log opcode name and inode

[virtiofs-bot at sinrega.org]

When log-level is debug, log the opcode name (instead of just the
number) and the inode for each request.  Example:

```
[2022-02-11T17:04:34Z INFO  virtiofsd] Waiting for vhost-user socket connection...
[2022-02-11T17:04:37Z INFO  virtiofsd] Client connected, servicing requests
[2022-02-11T17:04:41Z DEBUG virtiofsd] HIPRIO_QUEUE_EVENT
[2022-02-11T17:04:41Z DEBUG virtiofsd] QUEUE_EVENT
[2022-02-11T17:06:39Z DEBUG virtiofsd] QUEUE_EVENT
[2022-02-11T17:06:39Z DEBUG virtiofsd::server] Received request: opcode=Init, inode=0
[2022-02-11T17:06:39Z DEBUG virtiofsd::server] Replying OK, header: OutHeader { len: 80, error: 0, unique: 2 }
[2022-02-11T17:06:39Z DEBUG virtiofsd] QUEUE_EVENT
[2022-02-11T17:06:39Z DEBUG virtiofsd::server] Received request: opcode=Getxattr, inode=1
[2022-02-11T17:06:39Z DEBUG virtiofsd::server] Replying ERROR, header: OutHeader { len: 16, error: -38, unique: 4 }
```
---
https://gitlab.com/virtio-fs/virtiofsd/-/merge_requests/93