Maybe someone will find this kext useful...
Most of info is given at https://github.com/dukzcry/osx-goodies/blob/master/watchdog/README.mkd. There are some downsides of this solution mentioned in it. Please read through carefully before trying.
Those, who run server under OS X with requirement on high availability may agree with me that just passing of "panic_restart_timeout" flag to the kernel may be not enough to satisfy this requirement So here is the driver called iTCOWatchdog for watchdog timer which is present on most of systems with Intel chipset. It will do hard reboot of your machine either on KP and machine hang. Configured by default to react on scheduler failure too.
Installer and debug version of kext https://www.osx86.net/files/file/582-itcowatchdogkext/