Pod that explicitly opted into "seLinuxChangePolicy: Recursive" should not
report conflicts with another SELinux labels. They will only report a
conflict with other Pods using the same volume with "seLinuxChangePolicy:
Mount" (or nil).
A real SELinuxOptionsToFileLabel function needs access to host's
/etc/selinux to read the defaults. This is not possible in
kube-controller-manager that often runs in a container and does not have
access to /etc on the host. Even if it had, it could run on a different
Linux distro than worker nodes.
Therefore implement a custom SELinuxOptionsToFileLabel that does not
default fields in SELinuxOptions and uses just fields provided by the Pod.
Since the controller cannot default empty SELinux label components,
treat them as incomparable.
Example: "system_u:system_r:container_t:s0:c1,c2" *does not* conflict with ":::s0:c1,c2",
because the node that will run such a Pod may expand "":::s0:c1,c2" to "system_u:system_r:container_t:s0:c1,c2".
However, "system_u:system_r:container_t:s0:c1,c2" *does* conflict with ":::s0:c98,c99".
* Remove Controller.recorder field, there already is eventRecorder.
* Start the event broadcaster in Run(), to save a bit of CPU and memory
when something initializes the controller, but does not Run() it.
* Log events with log level 3, as the other contollers usually do.
* Use StartStructuredLogging(), which looks fancier than StartLogging
