staging: greybus: light: Use kzalloc for allocating only one thing

Use kzalloc rather than kcalloc(1,...)

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
@@

- kcalloc(1,
+ kzalloc(
          ...)
// </smpl>
Reviewed-by: Alex Elder <elder@linaro.org>
Reviewed-by: Rui Miguel Silva <rmfrfs@gmail.com>
Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Link: https://lore.kernel.org/r/20201230013706.28698-1-zhengyongjun3@huawei.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/greybus/light.c

@@ -290,8 +290,7 @@ static int channel_attr_groups_set(struct gb_channel *channel,
 	channel->attrs = kcalloc(size + 1, sizeof(*channel->attrs), GFP_KERNEL);
 	if (!channel->attrs)
 		return -ENOMEM;
-	channel->attr_group = kcalloc(1, sizeof(*channel->attr_group),
-				      GFP_KERNEL);
+	channel->attr_group = kzalloc(sizeof(*channel->attr_group), GFP_KERNEL);
 	if (!channel->attr_group)
 		return -ENOMEM;
 	channel->attr_groups = kcalloc(2, sizeof(*channel->attr_groups),