rtc: m48t86: add DT support for m48t86

Add OF ID match table.

Acked-by: Arnd Bergmann <[e-mail]>
Reviewed-by: Linus Walleij <[e-mail]>
Link: https://lore.kernel.org/lkml/[e-mail]/
Signed-off-by: Nikita Shubin <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Alexandre Belloni <[e-mail]>

drivers/rtc/rtc-m48t86.c

···
  */
 
 #include <linux/module.h>
+#include <linux/mod_devicetable.h>
 #include <linux/rtc.h>
 #include <linux/platform_device.h>
 #include <linux/bcd.h>
···
 	return 0;
 }
 
+static const struct of_device_id m48t86_rtc_of_ids[] = {
+	{ .compatible = "st,m48t86" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, m48t86_rtc_of_ids);
+
 static struct platform_driver m48t86_rtc_platform_driver = {
 	.driver		= {
 		.name	= "rtc-m48t86",
+		.of_match_table = m48t86_rtc_of_ids,
 	},
 	.probe		= m48t86_rtc_probe,
 };