[media] pvrusb2: check for allocation failures

This function returns NULL on failure so lets do that if kzalloc()
fails.  There is a separate problem that the caller for this function
doesn't check for errors...

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-By: Mike Isely <isely@pobox.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/pvrusb2/pvrusb2-std.c b/drivers/media/video/pvrusb2/pvrusb2-std.c
index ca9f83a..35c8b40 100644
--- a/drivers/media/video/pvrusb2/pvrusb2-std.c
+++ b/drivers/media/video/pvrusb2/pvrusb2-std.c
@@ -370,7 +370,11 @@
 
 	stddefs = kzalloc(sizeof(struct v4l2_standard) * std_cnt,
 			  GFP_KERNEL);
-	for (idx = 0; idx < std_cnt; idx++) stddefs[idx].index = idx;
+	if (!stddefs)
+		return NULL;
+
+	for (idx = 0; idx < std_cnt; idx++)
+		stddefs[idx].index = idx;
 
 	idx = 0;