Use zalloc instead of calloc(1, ...)

Signed-off-by: Bryce Harrington <bryce@osg.samsung.com>
Reviewed-by: Marek Chalupa <mchqwerty@gmail.com>
diff --git a/src/pixman-renderer.c b/src/pixman-renderer.c
index 2c26c3a..530e2ed 100644
--- a/src/pixman-renderer.c
+++ b/src/pixman-renderer.c
@@ -622,8 +622,8 @@
 	struct pixman_surface_state *ps;
 	struct pixman_renderer *pr = get_renderer(surface->compositor);
 
-	ps = calloc(1, sizeof *ps);
-	if (!ps)
+	ps = zalloc(sizeof *ps);
+	if (ps == NULL)
 		return -1;
 
 	surface->renderer_state = ps;
@@ -701,7 +701,7 @@
 {
 	struct pixman_renderer *renderer;
 
-	renderer = calloc(1, sizeof *renderer);
+	renderer = zalloc(sizeof *renderer);
 	if (renderer == NULL)
 		return -1;
 
@@ -746,10 +746,11 @@
 WL_EXPORT int
 pixman_renderer_output_create(struct weston_output *output)
 {
-	struct pixman_output_state *po = calloc(1, sizeof *po);
+	struct pixman_output_state *po;
 	int w, h;
 
-	if (!po)
+	po = zalloc(sizeof *po);
+	if (po == NULL)
 		return -1;
 
 	/* set shadow image transformation */