Using ironic.api.wsgi:initialize_wsgi_app to provide custom config file
to ironic will prevent the oslo_backend to be set to threading and will
bypass the RLock on threading leading to race condition during threads
starts.
Instead, document a way to give config dir/file from environment
variables.
Change-Id: I2aabe72f4d28ec55727e06788d3a9d2976dda4bb
Signed-off-by: Arnaud M <arnaud.morin@gmail.com>
6e5984576d