Don't hard set infra-files in swift wsgi conf

The container for os-loganalyze to pull from should be configurable but
there was a bug in the wsgi.conf where we tried to hardset the container
and make it configurable at the same time. Just make it configurable so
that the value in the config is correct.

Change-Id: I56de3ed87d6c27ac1723ffa2812e53cac31b5f40
Merge "Don't hard set infra-files in swift wsgi conf"