drop the "container" param from ap_walk_config(). callers should simply

drop the "container" param from ap_walk_config(). callers should simply
    pass the first child, rather than expecting the walker to do it.
remove the nasty "static" variable inside ap_walk_config(). it now walks the
    tree provided with no worries about bumping up/down levels.
minor refactor between ap_walk_config() and ap_walk_config_sub() to clean up
    some logic and clarify the code.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@85025 13f79535-47bb-0310-9956-ffa450edef68