Fixes for NT dynamic linking.

include/ac/assert.h

include/ac/errno.h

include/ac/setproctitle.h

include/ac/socket.h

include/ac/stdarg.h

include/ac/string.h

include/ac/unistd.h

include/avl.h

include/disptmpl.h

include/getopt-compat.h

include/lber.h

include/lber_pvt.h

include/ldap.h

include/ldap_cdefs.h

include/ldap_log.h

include/ldap_pvt.h

include/ldap_pvt_thread.h

include/ldap_schema.h

include/ldbm.h

include/ldif.h