rtc: rv8803: fix possible race condition

The probe function is not allowed to fail after registering the RTC. Call
rtc_register_device() at the end.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
diff --git a/drivers/rtc/rtc-rv8803.c b/drivers/rtc/rtc-rv8803.c
index 6fb5041..29fc3d2 100644
--- a/drivers/rtc/rtc-rv8803.c
+++ b/drivers/rtc/rtc-rv8803.c
@@ -590,14 +590,6 @@
 		}
 	}
 
-	rv8803->rtc->ops = &rv8803_rtc_ops;
-	rv8803->rtc->nvram_old_abi = true;
-	err = rtc_register_device(rv8803->rtc);
-	if (err)
-		return err;
-
-	rtc_nvmem_register(rv8803->rtc, &nvmem_cfg);
-
 	err = rv8803_write_reg(rv8803->client, RV8803_EXT, RV8803_EXT_WADA);
 	if (err)
 		return err;
@@ -608,6 +600,14 @@
 		return err;
 	}
 
+	rv8803->rtc->ops = &rv8803_rtc_ops;
+	rv8803->rtc->nvram_old_abi = true;
+	err = rtc_register_device(rv8803->rtc);
+	if (err)
+		return err;
+
+	rtc_nvmem_register(rv8803->rtc, &nvmem_cfg);
+
 	rv8803->rtc->max_user_freq = 1;
 
 	return 0;