lchan: Every SS_LCHAN signal now sends a struct lchan_sig_data

The SS_LCHAN signals now always include the lchan_sig_data. For
the measurement report it will optionally include the measurement
report as well. Attempt to update all handlers of this signal as well
diff --git a/openbsc/include/openbsc/signal.h b/openbsc/include/openbsc/signal.h
index dfb837d..a235cfb 100644
--- a/openbsc/include/openbsc/signal.h
+++ b/openbsc/include/openbsc/signal.h
@@ -182,6 +182,13 @@
 	int paging_result;
 };
 
+struct lchan_signal_data {
+	/* The lchan the signal happened on */
+	struct gsm_lchan *lchan;
+	/* Measurement reports on this lchan */
+	struct gsm_meas_rep *mr;
+};
+
 enum signal_ns {
 	S_NS_RESET,
 	S_NS_BLOCK,