meta-google: watchdog: Increase timeout to 120s

The timeout of 60s is causing tests with Qemu to fail for gBMC. This is
not an issue with real machines. Increase the timeout to avoid the
issue.

Change-Id: Ie1c206349dc21eecbfb5fd7350b4f643b08d9708
Signed-off-by: Willy Tu <wltu@google.com>
diff --git a/meta-google/recipes-google/systemd/files/40-system.conf b/meta-google/recipes-google/systemd/files/40-system.conf
index 601e0a5..19347e9 100644
--- a/meta-google/recipes-google/systemd/files/40-system.conf
+++ b/meta-google/recipes-google/systemd/files/40-system.conf
@@ -1,4 +1,4 @@
 [Manager]
 DefaultMemoryAccounting=yes
-RuntimeWatchdogSec=60s
+RuntimeWatchdogSec=120s
 WatchdogDevice=/dev/watchdog