docs: Use more accurate wording for /dev hostPath behavior

I got lazy when I first added this section in 5c21b1f, so updating the
language to specify that any non-regular host file (under /dev) qualifies,
not just devices.

This matches the actual code, see:

330bfff4be/src/runtime/virtcontainers/mount.go (L57-L83)

Signed-off-by: Aurélien Bombo <abombo@microsoft.com>

docs/Limitations.md

@@ -187,9 +187,10 @@ different compared to `runc` containers:
 into the guest and exposes it directly to the container.
 
 **Mounting guest devices**: When the source path of a hostPath volume is
-under `/dev`, and the path either corresponds to a host device or is not
-accessible by the Kata shim, the Kata agent bind mounts the source path
-directly from the *guest* filesystem into the container.
+under `/dev` (or `/dev` itself), and the path corresponds to a
+non-regular file (i.e., a device, directory, or any other special file)
+or is not accessible by the Kata shim, the Kata agent bind mounts the
+source path directly from the *guest* filesystem into the container.
 
 [runtime-config]: /src/runtime/README.md#configuration
 [k8s-hostpath]: https://kubernetes.io/docs/concepts/storage/volumes/#hostpath