CPLD 2.2 removed board watch dog support due to the limitation of CPLD
capacity after adding all the requested features, such as switch overriding.
There is no pin-compatible upgrade part available for current PCB design.
So remove codes related to it.

Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>