change builtin passphrase prompt to use stdout rather than stderr.

and switch to using apr_file api for portability.
stderr has already been redirected to the error_log.
rather than attempting to temporarily rehook it to the terminal,
we print the prompt to stdout before EVP_read_pw_string turns
off tty echo.  which is also more portable.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk/modules/ssl@93586 13f79535-47bb-0310-9956-ffa450edef68