ARM: dts: msm: Add watchdog dt node for sdmshrike

Add watchdog bark and bite thresholds used to configure watchdog timer
on sdmshrike. If the watchdog is not pet at regular specified intervals,
the system is assumed to be un-responsive and need to be reset.

Change-Id: I57656152a898e3bf8c3bb2e57d85ce93109fd01a
Signed-off-by: Jeevan Shriram <jshriram@codeaurora.org>