Added the ability to configuring the path to an RNG device

Unhardcode settings related to rng devices in nova formula.
The path to an RNG (Random Number Generator) device that will be used
as the source of entropy on the host.

Change-Id: Ifaa71e8bc986143004d0f97298d53b290721f4e8
Related-Prod: PROD-26873 (PROD:26873)
diff --git a/nova/files/rocky/nova-compute.conf.Debian b/nova/files/rocky/nova-compute.conf.Debian
index 4621588..209758b 100644
--- a/nova/files/rocky/nova-compute.conf.Debian
+++ b/nova/files/rocky/nova-compute.conf.Debian
@@ -6243,6 +6243,9 @@
 # http://man7.org/linux/man-pages/man7/random.7.html.
 #  (string value)
 #rng_dev_path = /dev/urandom
+{%- if compute.get('libvirt', {}).rng_dev_path is defined %}
+rng_dev_path={{ compute.libvirt.rng_dev_path }}
+{%- endif %}
 
 # For qemu or KVM guests, set this option to specify a default machine type per
 # host architecture. You can find a list of supported machine types in your