virtio-queue: fix hyperlink in documentation

The new `cargo doc` pipeline in the CI highlighted the following issue:
    warning: this URL is not a hyperlink
      --> virtio-queue/src/desc/mod.rs:16:5
       |
    16 | /// https://docs.oasis-open.org/virtio/virtio/v1.3/csd01/virtio-v1.3-csd01.html#x1-720008
       |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
       |
       = note: bare URLs are not automatically turned into clickable links
       = note: `#[warn(rustdoc::bare_urls)]` on by default
    help: use an automatic link instead
       |
    16 | /// <https://docs.oasis-open.org/virtio/virtio/v1.3/csd01/virtio-v1.3-csd01.html#x1-720008>
       |     +                                                                                     +

    warning: `virtio-queue` (lib doc) generated 1 warning (run `cargo fix --lib -p virtio-queue` to apply 1 suggestion)

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>

Author: stefano-garzarella

virtio-queue/src/desc/mod.rs

@@ -13,7 +13,7 @@ pub type Descriptor = RawDescriptor;
 /// This is a unified representation of the memory layout order
 /// for packed descriptors and split descriptors.
 /// This type corresponds to struct virtq_desc, see:
-/// https://docs.oasis-open.org/virtio/virtio/v1.3/csd01/virtio-v1.3-csd01.html#x1-720008
+/// <https://docs.oasis-open.org/virtio/virtio/v1.3/csd01/virtio-v1.3-csd01.html#x1-720008>
 #[repr(C)]
 #[derive(Clone, Copy, Debug, Default)]
 pub struct RawDescriptor(Le64, Le32, Le16, Le16);