HostRestrictingAuthorizationFilter should pass through requests if they don't access WebHDFS API

After HDFS-15320, HostRestrictingAuthorizationFilter returns 404 error if the request doesn't access WebHDFS API.
With this change, the endpoints, such as /conf and /jmx are no longer visible. This is very inconvenient for administrators.
HostRestrictingAuthorizationFilter should pass through requests if they don't access WebHDFS API.

This issue is reported by hadachi.