src/signal.c: cosmetic: use talloc_zero()

Change-Id: I55c6249b0c4c82d5a181001e945ff2eca6e9ca36
diff --git a/src/signal.c b/src/signal.c
index 188876b..7e53e83 100644
--- a/src/signal.c
+++ b/src/signal.c
@@ -67,12 +67,10 @@
 {
 	struct signal_handler *sig_data;
 
-	sig_data = talloc(tall_sigh_ctx, struct signal_handler);
+	sig_data = talloc_zero(tall_sigh_ctx, struct signal_handler);
 	if (!sig_data)
 		return -ENOMEM;
 
-	memset(sig_data, 0, sizeof(*sig_data));
-
 	sig_data->subsys = subsys;
 	sig_data->data = data;
 	sig_data->cbfn = cbfn;