[WATCHDOG] hpwdt: Use dmi_walk() instead of own copy

We can simplify the code by deleting all of the duplicated DMI table
walking code and using the kernel's existing dmi_walk() interface to
find the DMI entry the driver is looking for.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
Acked-by: Thomas Mingarelli <Thomas.Mingarelli@hp.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>