malloc + memset -> zalloc

And for clients using the xmalloc helper, use xzalloc.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
diff --git a/src/compositor.c b/src/compositor.c
index 19d84af..3213a7b 100644
--- a/src/compositor.c
+++ b/src/compositor.c
@@ -1077,9 +1077,7 @@
 		buffer = container_of(listener, struct weston_buffer,
 				      destroy_listener);
 	} else {
-		buffer = malloc(sizeof *buffer);
-		memset(buffer, 0, sizeof *buffer);
-
+		buffer = zalloc(sizeof *buffer);
 		buffer->resource = resource;
 		wl_signal_init(&buffer->destroy_signal);
 		buffer->destroy_listener.notify = weston_buffer_destroy_handler;