Patches for 2.1.23 to build on older systems

[pogma]

In order to build jabberd-2.1.23 we had to patch it a little.

1. configure.ac changes
   1. Check for stdarg.h in configure.
   2. Remove AC_PROG_GCC_TRADITIONAL (obsolete).
   3. Remove AC_FUNC_MALLOC, AC_FUNC_REALLOC - if they find malloc(0) does not return a valid pointer malloc will be defined to rpl_malloc, and no rpl_malloc is available. See http://www.gnu.org/software/autoconf/manual/autoconf.html#Particular-Functions
   4. Seems easier to use AC_SEARCH_LIBS for inet_ntop etc.
   5. Move the broken __ss_family check so that it appears after the check for struct sockaddr_storage.
   6. Check for socklen_t
   7. Fix --enable-pgsql

2. util/sha1.h: include inttypes.h instead of stdlib.h as it is more universally available.

3. acinclude.m4: TYPE_SOCKLEN_T check

4. subst/subst.h: include <stdarg.h> if available.

5. mio/mio.h: include "util/inaddr.h" for socklen_t ss_family etc etc.

6. c2s/c2s.c: Variable declarations not at beginning of block.

[smoku]

Fixes merged in [558-562].