6LoWPAN: TCP send logic was returning a failure in one case when, in fact, the send was successful.

configs/clicker2-stm32/README.txt

@@ -682,7 +682,10 @@ Configurations
         uncompressed UDP packet has a bad checksum.
 
         This required a change to assure that the destination IPv6 address
-        is not elided in the case of the star endpoint configuration.
+        is not elided in the case of the star endpoint configuration.  After
+        some additional fixes for byte ordering in 16-bit and 64-bit
+        compressed IPv6 addresses, the all tests are working as expectedd:
+        TCP, UDP, Telnet.
 
   nsh:
 

net/sixlowpan/sixlowpan_tcpsend.c

@@ -417,6 +417,7 @@ static uint16_t tcp_send_interrupt(FAR struct net_driver_s *dev,
            * actually sent.
            */
 
+          sinfo->s_result = sinfo->s_sent;
           goto end_wait;
         }