Update to 5.4

- Make this compile on amd64
- Don't silently look for libraries when we don't need them.  This should fix
  PR 39318
- Add missing depends on apr

Release 5.4
###########
* Fixes to the http modules as some Apache installations are picky
* The MySQL module also works with mysqld-5.0, updated
* Added AS/400 return code checks to pop3 module
* Fixed memory leaks in the http-form module.
* Implemented a proposal by Jean-Baptiste.BEAUFRETON (at) turbomeca.fr to
  check for "530 user unknown" message in the ftp module
* Added a performance patch by alejandro.mendiondo (at) baicom.com. This one
  needs stability testing!
* Beautification to remove compiler warnings of modern gcc

(adrianp)