Fix formatting of extra kernel options for Bifrost

Change-Id: I5aa1a32015bb0090689447f977d7840c9e5fefdd
Story: 2008714
Task: 42049

ansible/roles/kolla-bifrost/templates/bifrost.yml.j2

@@ -5,7 +5,7 @@ enabled_hardware_types: "{{ kolla_bifrost_enabled_hardware_types | join(',') }}"
 {% if kolla_bifrost_extra_kernel_options %}
 # List of extra kernel parameters for Bifrost's Ironic PXE configuration.
 # Default is empty.
-extra_kernel_options: "{{ kolla_bifrost_extra_kernel_options }}"
+extra_kernel_options: "{{ kolla_bifrost_extra_kernel_options | join(' ') }}"
 {% endif %}
 
 # IP address range for DHCP.

releasenotes/notes/fix-bifrost-ironic-extra-kernel-params-9ebdec1212ac9827.yaml

+---
+fixes:
+  - |
+    Fixes formatting of extra kernel options configured with
+    ``kolla_bifrost_extra_kernel_options`` when passed to Bifrost. See `story
+    2008714 <https://storyboard.openstack.org/#!/story/2008714>`__ for details.