watchdog: pass in default timeout on service start

This commit will allow other meta layers to easily override the default
timeout on watchdog start. Without passing the --min_interval option
there is no way currently for other layers to change this on startup.

Set the default of 30000 milliseconds to match the current default
defined within the phosphor-dbus-interface.

Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
Change-Id: I6a25d5dd3da5704113c3f77d6f9737e0705b3d01
diff --git a/meta-phosphor/recipes-phosphor/watchdog/phosphor-watchdog/obmc/watchdog/poweron b/meta-phosphor/recipes-phosphor/watchdog/phosphor-watchdog/obmc/watchdog/poweron
index 591d6dc..a972a47 100644
--- a/meta-phosphor/recipes-phosphor/watchdog/phosphor-watchdog/obmc/watchdog/poweron
+++ b/meta-phosphor/recipes-phosphor/watchdog/phosphor-watchdog/obmc/watchdog/poweron
@@ -1,3 +1,4 @@
 DEVPATH=/xyz/openbmc_project/watchdog/host0
 SERVICE=xyz.openbmc_project.Watchdog
 TARGET=obmc-host-timeout@0.target
+TIMEOUT_IN_MSEC=30000
diff --git a/meta-phosphor/recipes-phosphor/watchdog/phosphor-watchdog/phosphor-watchdog@.service b/meta-phosphor/recipes-phosphor/watchdog/phosphor-watchdog/phosphor-watchdog@.service
index aab1ddb..1f65902 100644
--- a/meta-phosphor/recipes-phosphor/watchdog/phosphor-watchdog/phosphor-watchdog@.service
+++ b/meta-phosphor/recipes-phosphor/watchdog/phosphor-watchdog/phosphor-watchdog@.service
@@ -4,4 +4,4 @@
 [Service]
 Restart=no
 EnvironmentFile={envfiledir}/obmc/watchdog/%I
-ExecStart=/usr/bin/phosphor-watchdog --continue --service=${{SERVICE}} --path=${{DEVPATH}} --target=${{TARGET}}
+ExecStart=/usr/bin/phosphor-watchdog --continue --service=${{SERVICE}} --path=${{DEVPATH}} --target=${{TARGET}} --min_interval=${{TIMEOUT_IN_MSEC}}