Allow any mutex to accept a 'filename' ... and always root it to the

  Allow any mutex to accept a 'filename' ... and always root it to the
  server root unless we are using posixsem, which can't handle big paths.
  This reorganization should make the code much more readable because
  all of the common code is at the beginning and end of the function,
  simplifing the long conditional test case block.

  This patch allows SSLMutex default:logs/ssl_mutex syntax.  It also
  removes the mod_ssl historical '.pid' suffixes - that isn't how Apache2
  specifies files.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@99094 13f79535-47bb-0310-9956-ffa450edef68