net/tcp: fix build break if enable NET_TCP_NO_STACK

devif/ipv6_input.c: In function 'ipv6_input':
devif/ipv6_input.c:59:33: error: 'TCPIPv6BUF' undeclared (first use in this function); did you mean 'IPv6BUF'?
   59 | #define PAYLOAD ((FAR uint8_t *)TCPIPv6BUF)
      |                                 ^~~~~~~~~~
devif/ipv6_input.c:302:14: note: in expansion of macro 'PAYLOAD'
  302 |   payload  = PAYLOAD;     /* Assume payload starts right after IPv6 header */
      |

Signed-off-by: chao an <anchao@xiaomi.com>

net/tcp/tcp.h

@@ -37,12 +37,19 @@
 #include <nuttx/net/net.h>
 #include <nuttx/wqueue.h>
 
-#if defined(CONFIG_NET_TCP) && !defined(CONFIG_NET_TCP_NO_STACK)
+#ifdef CONFIG_NET_TCP
 
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
 
+/* This is a helper pointer for accessing the contents of the tcp header */
+
+#define TCPIPv4BUF ((FAR struct tcp_hdr_s *)IPBUF(IPv4_HDRLEN))
+#define TCPIPv6BUF ((FAR struct tcp_hdr_s *)IPBUF(IPv6_HDRLEN))
+
+#ifndef CONFIG_NET_TCP_NO_STACK
+
 #define NET_TCP_HAVE_STACK 1
 
 /* Allocate a new TCP data callback */
@@ -104,11 +111,6 @@
 
 #define TCP_FAST_RETRANSMISSION_THRESH 3
 
-/* This is a helper pointer for accessing the contents of the tcp header */
-
-#define TCPIPv4BUF ((FAR struct tcp_hdr_s *)IPBUF(IPv4_HDRLEN))
-#define TCPIPv6BUF ((FAR struct tcp_hdr_s *)IPBUF(IPv6_HDRLEN))
-
 /****************************************************************************
  * Public Type Definitions
  ****************************************************************************/
@@ -2025,5 +2027,6 @@ void tcp_sendbuffer_notify(FAR struct tcp_conn_s *conn);
 }
 #endif
 
-#endif /* CONFIG_NET_TCP && !CONFIG_NET_TCP_NO_STACK */
+#endif /* !CONFIG_NET_TCP_NO_STACK */
+#endif /* CONFIG_NET_TCP */
 #endif /* __NET_TCP_TCP_H */