chore: mention virtio-rng in CHANGELOG

Add an entry for virtio-rng to the new features section of the
CHANGELOG.

Signed-off-by: Babis Chalios <[email protected]>

Author: bchalios

CHANGELOG.md

@@ -10,6 +10,8 @@
   as Neoverse N1.
 - Added a `cpu-template-helper` tool for assisting with creating and managing
   custom CPU templates.
+- Added support for the `virtio-rng` entropy device. The device is optional. A
+  single device can be enabled per VM using the `/entropy` endpoint.
 
 ### Fixed