btl tcp: Print number of endpoints on error

While trying to debug #3035, it's not clear whether there is
an issue with the modex data or printing the address list.
Print the number of endpoints on the error, which will help
determine which case is happening to Cisco.

Signed-off-by: Brian Barrett <bbarrett@amazon.com>

Author: bwbarrett

opal/mca/btl/tcp/btl_tcp_proc.c

@@ -929,6 +929,7 @@ void mca_btl_tcp_proc_accept(mca_btl_tcp_proc_t* btl_proc, struct sockaddr* addr
                        btl_proc->proc_opal->proc_hostname,
                        OPAL_NAME_PRINT(btl_proc->proc_opal->proc_name),
                        opal_net_get_hostname((struct sockaddr*)addr),
+                       btl_proc->proc_endpoint_count,
                        (NULL == addr_str) ? "NONE" : addr_str);
         if (NULL != addr_str) {
             free(addr_str);

opal/mca/btl/tcp/help-mpi-btl-tcp.txt

@@ -99,7 +99,7 @@ hopefully be able to continue).
   Local PID:           %d
   Peer hostname:       %s (%s)
   Source IP of socket: %s
-  Known IPs of peer:   %s
+  Known IPs of peer (%d):   %s
 #
 [socket flag fail]
 WARNING: Open MPI failed to get or set flags on a TCP socket.  This