Deprecates the existing "ironic-agent" element in DIB

The "ironic-agent" is copied to ironic-python-agent-builder and
hence it is deprecated from DIB.

Remove from functional testing

Change-Id: Ibc4f75b9d7e2a31994fc86d05bd57975f00fb74f
Task: 36198
Story: 2005114

.zuul.d/jobs.yaml

@@ -26,7 +26,6 @@
         # Fedora paused until dnf segfaults resolved:
         #  https://bugzilla.redhat.com/show_bug.cgi?id=1758737
         #  https://bugzilla.redhat.com/show_bug.cgi?id=1761282
-        # - fedora-minimal/build-succeeds
         # - ironic-agent/build-succeeds-fedora
         # - pip-and-virtualenv/source-install-fedora
         - pip-and-virtualenv/source-install-ubuntu

diskimage_builder/elements/ironic-agent/README.rst

@@ -1,6 +1,13 @@
 ============
 ironic-agent
 ============
+warning::
+ This element is deprecated and copied to
+ ironic-python-agent-builder and can be found at:
+ https://opendev.org/openstack/ironic-python-agent-builder/dib/
+ The ramdisk can be build from the ironic-python-agent-builder and
+ the "ironic-element" in diskimage-builder is deprecated.
+
 Builds a ramdisk with ironic-python-agent.  More information can be found at:
     https://opendev.org/openstack/ironic-python-agent/
 

releasenotes/notes/deprecate-ironic-agent-element.yaml

@@ -0,0 +1,6 @@
+---
+deprecations:
+
+  - The "ironic-agent" element can now be found at
+    ironic-python-agent-builder to build the ramdisk.
+    This element is deprecated from diskimage-builder.