mptcp: print out reset infos of MP_RST

This patch printed out the reset infos, reset_transient and reset_reason,
of MP_RST in mptcp_parse_option() to show that MP_RST is received.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/mptcp/options.c

@@ -336,6 +336,8 @@ static void mptcp_parse_option(const struct sk_buff *skb,
 		flags = *ptr++;
 		mp_opt->reset_transient = flags & MPTCP_RST_TRANSIENT;
 		mp_opt->reset_reason = *ptr;
+		pr_debug("MP_RST: transient=%u reason=%u",
+			 mp_opt->reset_transient, mp_opt->reset_reason);
 		break;
 
 	case MPTCPOPT_MP_FAIL: