watchdog: fix set_timeout operations

Since we changed the behaviour of the set_timeout operation in the
watchdog API, we need to change the allready converted drivers so
that they update the timeout field at the end of the set_timeout
operation.

Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
diff --git a/drivers/watchdog/jz4740_wdt.c b/drivers/watchdog/jz4740_wdt.c
index 28af416..978615e 100644
--- a/drivers/watchdog/jz4740_wdt.c
+++ b/drivers/watchdog/jz4740_wdt.c
@@ -109,6 +109,7 @@
 
 	writeb(0x1, drvdata->base + JZ_REG_WDT_COUNTER_ENABLE);
 
+	wdt_dev->timeout = new_timeout;
 	return 0;
 }