OpenSSL: BoringSSL has SSL_get_client_random(), etc.

BoringSSL added OpenSSL 1.1.0's SSL_get_client_random() and friends in
working towards opaquifying the SSL struct. But it, for the moment,
still looks more like 1.0.2 than 1.1.0 and advertises
OPENSSL_VERSION_NUMBER as such. This means that there is no need to
define those in BoringSSL and defining them causes conflicts. (C does
not like having static and non-static functions with the same name.)

As requested, this is conditioned on defined(BORINGSSL_API_VERSION) so
wpa_supplicant may continue to support older BoringSSLs for a time.
(BoringSSL revisions without the accessors predate BoringSSL maintaining
a BORINGSSL_API_VERSION.)

Also add a missing opensslv.h include. tls_openssl.c is sensitive to
OPENSSL_VERSION_NUMBER, so it should include the header directly rather
than rely on another header to do so.

Signed-off-by: David Benjamin <davidben@google.com>

src/crypto/tls_openssl.c

@@ -18,6 +18,7 @@
 
 #include <openssl/ssl.h>
 #include <openssl/err.h>
+#include <openssl/opensslv.h>
 #include <openssl/pkcs12.h>
 #include <openssl/x509v3.h>
 #ifndef OPENSSL_NO_ENGINE
@@ -51,10 +52,13 @@ typedef int stack_index_t;
 #endif /* OPENSSL_NO_TLSEXT */
 #endif /* SSL_set_tlsext_status_type */
 
-#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
+#if (OPENSSL_VERSION_NUMBER < 0x10100000L || \
+     defined(LIBRESSL_VERSION_NUMBER)) &&    \
+    !defined(BORINGSSL_API_VERSION)
 /*
  * SSL_get_client_random() and SSL_get_server_random() were added in OpenSSL
- * 1.1.0. Provide compatibility wrappers for older versions.
+ * 1.1.0 and newer BoringSSL revisions. Provide compatibility wrappers for
+ * older versions.
  */
 
 static size_t SSL_get_client_random(const SSL *ssl, unsigned char *out,