Revision 1774748

Make Serf compile and tests pass when the symbols OPENSSL_NO_TLSEXT
and/or OPENSSL_NO_OCSP are defined.

These symbols are used in several places to enclose conditional blocks
of code, but some checks were missing.

* buckets/ssl_buckets.c
  (ocsp_callback): Make conditional on OPENSSL_NO_OCSP, too.
  (serf_ssl_check_cert_status_request): Likelwise.

* test/MockHTTPinC/MockHTTP_server.c
  (ocspCreateResponse, ocspStatusCallback): Make conditional on
   OPENSSL_NO_TLSEXT and OPENSSL_NO_OCSP.
  (alpn_select_callback): Make conditional on OPENSSL_NO_TLSEXT.
  (initSSLCtx): Don't use alpn_select_callback depending on OPENSSL_NO_TLSEXT.
   Likewise for ocspStatusCallback, which also depends on OPENSSL_NO_OCSP.

* test/test_ssl.c
  (test_ss l_ocsp_response_error_and_override): Do not check for stapled
   OCSP response depending on OPENSSL_NO_TLSEXT and OPENSSL_NO_OCSP.
  (http11_select_protocol, http11_alpn_setup): Make conditional on
   OPENSSL_NO_TLSEXT and OPENSSL_NO_OCSP.
  (test_ssl_alpn_negotiate): Make test no-op depending on OPENSSL_NO_TLSEXT.