openssl: fix BoringSSL symbol conflicts with LDAP and Schannel

Same issue as here [1], but this time when building curl with BoringSSL
for Windows with LDAP(S) or Schannel support enabled.

Apply the same fix [2] for these source files as well.

This can also be fixed by moving `#include "urldata.h"` _before_
including `winldap.h` and `schnlsp.h` respectively. This seems like
a cleaner fix, though I'm not sure why it works and if it has any
downside.

[1] https://github.com/curl/curl/issues/5669
[2] fbe07c6829

Co-authored-by: Jay Satiro
Closes #9110

lib/ldap.c

@@ -37,6 +37,18 @@
  * OpenLDAP library versions, USE_OPENLDAP shall not be defined.
  */
 
+/* Wincrypt must be included before anything that could include OpenSSL. */
+#if defined(USE_WIN32_CRYPTO)
+#include <wincrypt.h>
+/* Undefine wincrypt conflicting symbols for BoringSSL. */
+#undef X509_NAME
+#undef X509_EXTENSIONS
+#undef PKCS7_ISSUER_AND_SERIAL
+#undef PKCS7_SIGNER_INFO
+#undef OCSP_REQUEST
+#undef OCSP_RESPONSE
+#endif
+
 #ifdef USE_WIN32_LDAP           /* Use Windows LDAP implementation. */
 # include <winldap.h>
 # ifndef LDAP_VENDOR_NAME

lib/vtls/schannel.h

@@ -28,6 +28,18 @@
 
 #ifdef USE_SCHANNEL
 
+/* Wincrypt must be included before anything that could include OpenSSL. */
+#if defined(USE_WIN32_CRYPTO)
+#include <wincrypt.h>
+/* Undefine wincrypt conflicting symbols for BoringSSL. */
+#undef X509_NAME
+#undef X509_EXTENSIONS
+#undef PKCS7_ISSUER_AND_SERIAL
+#undef PKCS7_SIGNER_INFO
+#undef OCSP_REQUEST
+#undef OCSP_RESPONSE
+#endif
+
 #include <schnlsp.h>
 #include <schannel.h>
 #include "curl_sspi.h"