Add support for Intersil isl1208 RTC

Signed-off-by: Tor Krill <tor@excito.com>
diff --git a/README b/README
index 491397a..b230fde 100644
--- a/README
+++ b/README
@@ -669,6 +669,7 @@
 		CONFIG_RTC_DS1337	- use Maxim, Inc. DS1337 RTC
 		CONFIG_RTC_DS1338	- use Maxim, Inc. DS1338 RTC
 		CONFIG_RTC_DS164x	- use Dallas DS164x RTC
+		CONFIG_RTC_ISL1208	- use Intersil ISL1208 RTC
 		CONFIG_RTC_MAX6900	- use Maxim, Inc. MAX6900 RTC
 
 		Note that if the RTC uses I2C, then the I2C interface