Log "access denied" messages with 'warning' level instead of 'error' in 
mod_authz_svn: this message logged in properly configured server when user
requests log or directory without access to some subdirectories. Such 
situation is not error.

* subversion/mod_authz_svn/mod_authz_svn.c
  (log_access): Use APLOG_WARNING for access denied message instead of 
   APLOG_ERR.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1562417 13f79535-47bb-0310-9956-ffa450edef68