Use [x]zalloc instead of [x]malloc + memset

Signed-off-by: Ryo Munakata <ryomnktml@gmail.com>
Reviewed-by: Derek Foreman <derekf@osg.samsung.com>
diff --git a/clients/editor.c b/clients/editor.c
index d0b7fee..7d388a4 100644
--- a/clients/editor.c
+++ b/clients/editor.c
@@ -687,8 +687,7 @@
 {
 	struct text_entry *entry;
 
-	entry = xmalloc(sizeof *entry);
-	memset(entry, 0, sizeof *entry);
+	entry = xzalloc(sizeof *entry);
 
 	entry->widget = widget_add_widget(editor->widget, entry);
 	entry->window = editor->window;
diff --git a/clients/subsurfaces.c b/clients/subsurfaces.c
index 32179db..b971fdf 100644
--- a/clients/subsurfaces.c
+++ b/clients/subsurfaces.c
@@ -498,8 +498,7 @@
 {
 	struct triangle *tri;
 
-	tri = xmalloc(sizeof *tri);
-	memset(tri, 0, sizeof *tri);
+	tri = xzalloc(sizeof *tri);
 
 	tri->egl = egl;
 	tri->widget = window_add_subsurface(window, tri,
@@ -720,8 +719,7 @@
 {
 	struct demoapp *app;
 
-	app = xmalloc(sizeof *app);
-	memset(app, 0, sizeof *app);
+	app = xzalloc(sizeof *app);
 
 	app->egl = egl_state_create(display_get_display(display));