PR#45722: if we get EACCESS in the directory walk, give the hint that's in 1.3

PR#45722: if we get EACCESS in the directory walk, give the hint that's in 1.3
about search permissions on intermediate directories.  I left the prefix of the message
as "denied" instead of "failed" to satisfy web searches.

The extended error text was added to 1.3.x but not trunk in
  http://svn.apache.org/viewvc?view=revision&revision=99781

This plagues users on IRC!

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1031307 13f79535-47bb-0310-9956-ffa450edef68