add some sofia debugging for the local SDP

Related to issue FS-4293.

src/mod/endpoints/mod_sofia/sofia_glue.c

@@ -2598,6 +2598,11 @@ switch_status_t sofia_glue_do_invite(switch_core_session_t *session)
 		tech_pvt->session_refresher = nua_no_refresher;
 	}
 
+	if (tech_pvt->local_sdp_str) {
+		switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(tech_pvt->session), SWITCH_LOG_DEBUG,
+						  "Local SDP:\n%s\n", tech_pvt->local_sdp_str);
+	}
+
 	if (sofia_use_soa(tech_pvt)) {
 		nua_invite(tech_pvt->nh,
 				   NUTAG_AUTOANSWER(0),