Remove unused build checks

Remove unused build checks

- yp_get_default_domain was part of ext/yp
- functions checks produce HAVE_function_name symbols. These checks are
  currently not used in php-src neither in the extensions out there.
- Removed symbols because they are not used in the code:
  - HAVE_GCVT
  - HAVE_PUTENV
  - HAVE_PUTENV
  - HAVE_SETVBUF
  - HAVE_TEMPNAM
  - HAVE_SIN (sin is also defined in C89 standard)
  - HAVE_SETSOCKOPT
  - HAVE_LOCKF
  - HAVE_ISASCII
  - HAVE_YP_GET_DEFAULT_DOMAIN (and other yp extension related unused checks)
  - HAVE_LINK
- HAVE_USLEEP is already defined in Windows configuration header
- HAVE_LIBBIND has not been used in php-src for a while anymore
- HAVE_GETHOSTNAME is duplicated in Windows configuration header

Closes GH-4417