Fix return value checking for BIO_sock_init

BIO_sock_init returns '-1' on error, not '0', so it's needed to check
explicitly istead of using '!'.
Reviewed-by: NTim Hudson <tjh@openssl.org>
Reviewed-by: NBernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/3766)

apps/s_socket.c

 /*
- * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2017 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the OpenSSL license (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy
@@ -62,7 +62,7 @@ int init_client(int *sock, const char *host, const char *port,
     const BIO_ADDRINFO *ai = NULL;
     int ret;
 
-    if (!BIO_sock_init())
+    if (BIO_sock_init() != 1)
         return 0;
 
     ret = BIO_lookup_ex(host, port, BIO_LOOKUP_CLIENT, family, type, protocol,
@@ -161,7 +161,7 @@ int do_server(int *accept_sock, const char *host, const char *port,
     BIO_ADDRINFO *res = NULL;
     int ret = 0;
 
-    if (!BIO_sock_init())
+    if (BIO_sock_init() != 1)
         return 0;
 
     if (!BIO_lookup_ex(host, port, BIO_LOOKUP_SERVER, family, type, protocol,

test/handshake_helper.c

@@ -1135,7 +1135,7 @@ static int create_sctp_socks(int *ssock, int *csock)
     int ret = 0;
     int family = 0;
 
-    if (!BIO_sock_init())
+    if (BIO_sock_init() != 1)
         return 0;
 
     /*