Provide option to disable automatic reboots of host

[geissonator]

MFG and lab require the ability to disable the automated reboot that happens on a checkstop detection. This feature will enable that function. Need to define a property (host?) that can be set/cleared for this function.

[sivassrr]

@geissonator This will be only applicable to MFG and lab setup, right. Customer would not see this. Because Andrea was working/worked on reboot the host on detecting checkstop.

[geissonator]

Per a technical discussion today, we're just going to make one generic setting that people can set which will disable any type of automatic reboot. Re-titling and closing out #943

[tritzsm]

• Add new "Enable/disable automatic reboot" element to settingsd
• Need new "quiesce" target file from Andrew
• Modify host watchdog and host checkstop code to use the new target file
• Modify the host state code to monitor for the new quiesce target being entered

[spinler]

So how do I disable automatic reboots?

[tritzsm]

Set the auto_reboot settingsd parameter to "no" - as in
busctl call org.openbmc.settings.Host /org/openbmc/settings/host0 org.freedesktop.DBus.Properties Set sss org.openbmc.settings.Host auto_reboot no