rtc: pl030: drop needless struct pl030_rtc::rtc member

The memory pointed to by the ::rtc member is managed via devres, and
no code in this driver uses it past _probe().

We can drop it from the structure and just use a local temporary
variable, reducing runtime memory consumption by a few bytes.

Reviewed-by: Linus Walleij <[e-mail]>
Signed-off-by: André Draszik <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Alexandre Belloni <[e-mail]>

drivers/rtc/rtc-pl030.c

···
 #define RTC_CR_MIE	(1 << 0)
 
 struct pl030_rtc {
-	struct rtc_device	*rtc;
 	void __iomem		*base;
 };
 
···
 {
 	struct pl030_rtc *rtc;
 	int ret;
+	struct rtc_device *rtc_dev;
 
 	ret = amba_request_regions(dev, NULL);
 	if (ret)
···
 		goto err_rtc;
 	}
 
-	rtc->rtc = devm_rtc_allocate_device(&dev->dev);
-	if (IS_ERR(rtc->rtc)) {
-		ret = PTR_ERR(rtc->rtc);
+	rtc_dev = devm_rtc_allocate_device(&dev->dev);
+	if (IS_ERR(rtc_dev)) {
+		ret = PTR_ERR(rtc_dev);
 		goto err_rtc;
 	}
 
-	rtc->rtc->ops = &pl030_ops;
-	rtc->rtc->range_max = U32_MAX;
+	rtc_dev->ops = &pl030_ops;
+	rtc_dev->range_max = U32_MAX;
 	rtc->base = ioremap(dev->res.start, resource_size(&dev->res));
 	if (!rtc->base) {
 		ret = -ENOMEM;
···
 	if (ret)
 		goto err_irq;
 
-	ret = devm_rtc_register_device(rtc->rtc);
+	ret = devm_rtc_register_device(rtc_dev);
 	if (ret)
 		goto err_reg;