Increase default watchdog timeout to 10 minutes
Increase default watchdog timeout to 10 minutes

We have discovered some error cases within the memory diagnostics
step where a single hardware operation can take up to 6 minutes
to complete.  The code sends a watchdog ping before issuing any
command, but the current timeout (2 minutes) is insufficient to
handle these long commands.

Resolves boston-openpower/#1240

Change-Id: I4e27a45c927c014b5fcc28d4510c5996a7009953
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/59254
Tested-by: Jenkins Server <8e3f934e4c44875bc48d33da3ea13d93ba9a233f@us.ibm.com>
Tested-by: Jenkins OP Build CI <e610bd72261d3c0a48f1e8ae36832ab00774d426@us.ibm.com>
Tested-by: Jenkins OP HW <0eb0fff262f74a65a832afbcc7b153e391c9a3fd@us.ibm.com>
Tested-by: FSP CI Jenkins <aa9e4d9ac7cd25905e9c0dd36d4150516e73dd86@us.ibm.com>
Reviewed-by: William G. Hoffa <7dd6aa5e78423995d9d7c7ecada5b77ee07f88cc@us.ibm.com>
Reviewed-by: Daniel M. Crowell <912029ca9254ac7b5854e56910561d682e1fa2d0@us.ibm.com>

open-power/hostboot,open-power/hostboot,open-power/hostboot,open-power/hostboot,open-power/hostboot