ARM: dts: witherspoon: add Epson RX8900CE RTC module

This commit adds the relevant device tree entry for the Epson RX8900CE RTC module on the I2C bus.

Note that there are two options that we may need to set.

If there is no connected battery:
epson,vdet-disable;

If there is no trickle charge diode:
epson,vdet-disable;

These are currently left commented out in the commit.

---
arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts | 11 +++++++++++

1 file changed, 11 insertions(+)

index 328a9c4e189e..679d360272cc 100644
@@ -148,7 +148,18 @@
 

	/* TPM */
	/* 9552 */
+
	/* RTC */

+ rtc: rtc@32 {
+ compatible = "epson,rx8900"
+ reg = <0x32>;
+ /* If no battery, set this:
+ * epson,vdet-disable;
+ * If no trickle charge diode, set this:
+ * epson,vdet-disable;
+ */
+ };
+

	/* EEPROM */

	eeprom@51 {

2.9.3