rtc: sun6i: add support for R329 RTC

Allwinner R329 has a RTC with a similar time storage with H616 but a
slightly different clock part.

As we have already handled the R329 RTC clocks in the CCU driver, add a
compatible string to RTC driver to allow probing of the RTC.
Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20220626042756.58961-1-samuel@sholland.org

drivers/rtc/rtc-sun6i.c

@@ -875,6 +875,8 @@ static const struct of_device_id sun6i_rtc_dt_ids[] = {
 	{ .compatible = "allwinner,sun50i-h6-rtc" },
 	{ .compatible = "allwinner,sun50i-h616-rtc",
 		.data = (void *)RTC_LINEAR_DAY },
+	{ .compatible = "allwinner,sun50i-r329-rtc",
+		.data = (void *)RTC_LINEAR_DAY },
 	{ /* sentinel */ },
 };
 MODULE_DEVICE_TABLE(of, sun6i_rtc_dt_ids);