RTC driver for MC13783

MC13783 is a multifunction IS with an SPI interface to the host. This
driver handles the RTC controller in this chip.

Signed-off-by: Guennadi Liakhovetski <lg@denx.de>
diff --git a/README b/README
index 956c694..36ae0fb 100644
--- a/README
+++ b/README
@@ -672,6 +672,7 @@
 
 		CONFIG_RTC_MPC8xx	- use internal RTC of MPC8xx
 		CONFIG_RTC_PCF8563	- use Philips PCF8563 RTC
+		CONFIG_RTC_MC13783	- use MC13783 RTC
 		CONFIG_RTC_MC146818	- use MC146818 RTC
 		CONFIG_RTC_DS1307	- use Maxim, Inc. DS1307 RTC
 		CONFIG_RTC_DS1337	- use Maxim, Inc. DS1337 RTC