bio.h: fix number of arguments passed to BIO_ptr_ctrl()

Reviewed-by: NMatt Caswell <matt@openssl.org>
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/1520)

include/openssl/bio.h

@@ -365,9 +365,9 @@ struct bio_dgram_sctp_prinfo {
 #  define BIO_set_conn_port(b,port)     BIO_ctrl(b,BIO_C_SET_CONNECT,1,(char *)port)
 #  define BIO_set_conn_address(b,addr)  BIO_ctrl(b,BIO_C_SET_CONNECT,2,(char *)addr)
 #  define BIO_set_conn_ip_family(b,f)   BIO_int_ctrl(b,BIO_C_SET_CONNECT,3,f)
-#  define BIO_get_conn_hostname(b)      ((const char *)BIO_ptr_ctrl(b,BIO_C_GET_CONNECT,0,NULL))
-#  define BIO_get_conn_port(b)          ((const char *)BIO_ptr_ctrl(b,BIO_C_GET_CONNECT,1,NULL))
-#  define BIO_get_conn_address(b)       ((const BIO_ADDR *)BIO_ptr_ctrl(b,BIO_C_GET_CONNECT,2,NULL))
+#  define BIO_get_conn_hostname(b)      ((const char *)BIO_ptr_ctrl(b,BIO_C_GET_CONNECT,0))
+#  define BIO_get_conn_port(b)          ((const char *)BIO_ptr_ctrl(b,BIO_C_GET_CONNECT,1))
+#  define BIO_get_conn_address(b)       ((const BIO_ADDR *)BIO_ptr_ctrl(b,BIO_C_GET_CONNECT,2))
 #  define BIO_get_conn_ip_family(b)     BIO_ctrl(b,BIO_C_GET_CONNECT,3,NULL)
 #  define BIO_set_conn_mode(b,n)        BIO_ctrl(b,BIO_C_SET_CONNECT_MODE,(n),NULL)