rtc: rx8010js: add compatible string

Add compatible string used by Linux.
Allows for simpler syncing of device trees.

Signed-off-by: Robert Beckett <bob.beckett@collabora.com>
diff --git a/drivers/rtc/rx8010sj.c b/drivers/rtc/rx8010sj.c
index 2876692..82c5185 100644
--- a/drivers/rtc/rx8010sj.c
+++ b/drivers/rtc/rx8010sj.c
@@ -364,6 +364,7 @@
 
 static const struct udevice_id rx8010sj_rtc_ids[] = {
 	{ .compatible = "epson,rx8010sj-rtc" },
+	{ .compatible = "epson,rx8010" },
 	{ }
 };