Add Mark Goddard as an ironic release liaison

Mark has been an ironic contributor for some time,
is an Ironic core, and has assisted with releases
of ironic in the past. As such, we wish to confer
the rights to release ironic as needed

Thank you Mark for being awesome.

Change-Id: Idd4f2833c523dd8b64abe4d556120f4e46e29720

data/release_liaisons.yaml

@@ -50,6 +50,9 @@ ironic:
   - name: 'Dmitry Tantsur'
     irc: dtantsur
     email: dtantsur@protonmail.com
+  - name: 'Mark Goddard'
+    irc: mgoddard
+    email: mark@stackhpc.com
 keystone:
   - name: 'Kristi Nikolla'
     irc: knikolla