11849 listen of IPv6 address fails with EAFNOSUPPORT

*** 19,29 ****
   * CDDL HEADER END
   */
  
  /*
   * Copyright (c) 1991, 2010, Oracle and/or its affiliates. All rights reserved.
!  * Copyright (c) 2011, Joyent Inc. All rights reserved.
   * Copyright (c) 2011 Nexenta Systems, Inc. All rights reserved.
   * Copyright (c) 2013, 2017 by Delphix. All rights reserved.
   * Copyright 2014, OmniTI Computer Consulting, Inc. All rights reserved.
   */
  /* Copyright (c) 1990 Mentat Inc. */
--- 19,29 ----
   * CDDL HEADER END
   */
  
  /*
   * Copyright (c) 1991, 2010, Oracle and/or its affiliates. All rights reserved.
!  * Copyright 2019 Joyent, Inc.
   * Copyright (c) 2011 Nexenta Systems, Inc. All rights reserved.
   * Copyright (c) 2013, 2017 by Delphix. All rights reserved.
   * Copyright 2014, OmniTI Computer Consulting, Inc. All rights reserved.
   */
  /* Copyright (c) 1990 Mentat Inc. */
*** 4332,4346 ****
                          (void) strlog(TCP_MOD_ID, 0, 1, SL_ERROR|SL_TRACE,
                              "tcp_listen: bad state, %d", tcp->tcp_state);
                  }
                  return (-TOUTSTATE);
          } else {
-                 if (sa == NULL) {
                          sin6_t  addr;
                          sin_t *sin;
                          sin6_t *sin6;
  
                          ASSERT(IPCL_IS_NONSTR(connp));
                          /* Do an implicit bind: Request for a generic port. */
                          if (connp->conn_family == AF_INET) {
                                  len = sizeof (sin_t);
                                  sin = (sin_t *)&addr;
--- 4332,4346 ----
                          (void) strlog(TCP_MOD_ID, 0, 1, SL_ERROR|SL_TRACE,
                              "tcp_listen: bad state, %d", tcp->tcp_state);
                  }
                  return (-TOUTSTATE);
          } else {
                  sin6_t  addr;
                  sin_t *sin;
                  sin6_t *sin6;
  
+                 if (sa == NULL) {
                          ASSERT(IPCL_IS_NONSTR(connp));
                          /* Do an implicit bind: Request for a generic port. */
                          if (connp->conn_family == AF_INET) {
                                  len = sizeof (sin_t);
                                  sin = (sin_t *)&addr;