Install fakeroot for openafs packaeg builds

This installs fakeroot in the environment that we build openafs packages
in. This appears to be necessary to address:

  dpkg-buildpackage: error: fakeroot not found, either install the fakeroot
  package, specify a command with the -r option, or run this as root

Change-Id: Ic6b2045207de2317d801ba33b4c4181226f4310e

roles/infra-deb-package-build/tasks/main.yaml

@@ -5,6 +5,7 @@
       - devscripts
       - dpkg-dev
       - equivs # for mk-build-deps
+      - fakeroot
   become: yes
 
 - name: Make working directory