witherspoon: Enable phosphor-wdt-on-panic KERNEL_FEATURE

This allows the SoC to switch to the alternate BMC flash device when we
hit a kernel panic.

Tested: Instrumented which chip the system was currently booted from,
	booted a kernel with a broken root= configuration to trigger a
	panic, observed the system reboot due to a watchdog event,
	confirmed the chip used by the reboot was different.

Change-Id: I763ebadc3e26cc9e420e2469277970fbde974459
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
1 file changed