MIPS: ath79: fix maximum timeout

If the userland tries to set a timeout higher than the max_timeout, then we should fallback to max_timeout.

Signed-off-by: John Crispin <blogic@openwrt.org>

Index: linux-3.8.13/drivers/watchdog/ath79_wdt.c
===================================================================
--- linux-3.8.13.orig/drivers/watchdog/ath79_wdt.c	2013-07-14 14:10:19.198826462 +0200
+++ linux-3.8.13/drivers/watchdog/ath79_wdt.c	2013-07-14 14:25:40.810848422 +0200
@@ -103,10 +103,14 @@
 
 static int ath79_wdt_set_timeout(int val)
 {
-	if (val < 1 || val > max_timeout)
+	if (val < 1)
 		return -EINVAL;
 
-	timeout = val;
+	if (val > max_timeout)
+		timeout = max_timeout;
+	else
+		timeout = val;
+
 	ath79_wdt_keepalive();
 
 	return 0;