Add documentation for BIOS feature

In OCP4.9, the feature of configuring the BIOS of the worker node in the process of IPI has been added.
Add corresponding documents for detailed description.

Signed-off-by: Zhou Hao <[email protected]>

Author: zhouhao3

installing/installing_bare_metal_ipi/ipi-install-configuration-files.adoc

@@ -39,3 +39,7 @@ endif::[]
 ifeval::[{product-version} > 4.7]
 include::modules/ipi-install-configure-network-components-to-run-on-the-control-plane.adoc[leveloffset=+1]
 endif::[]
+
+ifeval::[{product-version} > 4.8]
+include::modules/ipi-install-configuring-bios-for-worker-node.adoc[leveloffset=+1]
+endif::[]

modules/ipi-install-configuring-bios-for-worker-node.adoc

@@ -0,0 +1,30 @@
+// Module included in the following assemblies:
+//
+// * installing/installing_bare_metal_ipi/ipi-install-configuration-files.adoc
+[id="configuring-bios-for-worker-node_{context}"]
+= Configuring BIOS for worker node
+
+The following procedure configures BIOS for the worker node during the installation process.
+
+.Procedure
+. Create manifests.
+. Modify the BMH file corresponding to the worker:
++
+----
+$ vim clusterconfigs/openshift/99_openshift-cluster-api_hosts-3.yaml
+----
+. Add the BIOS configuration to the `spec` section of the BMH file:
++
+----
+spec:
+  firmware:
+    simultaneousMultithreadingEnabled: true
+    sriovEnabled: true
+    virtualizationEnabled: true
+----
++
+[NOTE]
+====
+. Red Hat supports three BIOS configurations. See the link:https://github.com/openshift/baremetal-operator/blob/master/docs/api.md#firmware[BMH documentation] for details. Only servers with bmc type `irmc` are supported. Other types of servers are currently not supported.
+====
+. Create cluster.