Remove unneeded chown of /var/run/nova

Both upstart and systemd daemons are defined to create their own run
directories, and set the correct owners (see os-svc-daemon), so this
line can be removed. It causes an error for the package install b/c the
directory does not yet exist since the service has not been enabled and
started yet.

Change-Id: I598fe6d6ef55c997dcd5c9acfcc85ddac6826228