meta-phosphor: systemd: Enable watchdog pretimeout

This gives us the ability to try and panic the kernel prior to hitting a
hardware watchdog that gives us less information about the lockup. It's
safe to enable even if you have no pretimeout watchdog in your kernel.

Change-Id: I91b0c6f1069a64a657298142cff1b8eeffcb1dbc
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/meta-phosphor/recipes-core/systemd/systemd/40-hardware-watchdog.conf b/meta-phosphor/recipes-core/systemd/systemd/40-hardware-watchdog.conf
index c323a22..ecc930f 100644
--- a/meta-phosphor/recipes-core/systemd/systemd/40-hardware-watchdog.conf
+++ b/meta-phosphor/recipes-core/systemd/systemd/40-hardware-watchdog.conf
@@ -1,3 +1,5 @@
 [Manager]
 RuntimeWatchdogSec=120s
+RuntimeWatchdogPreSec=90s
+RuntimeWatchdogPreGovernor=panic
 WatchdogDevice=/dev/watchdog