ARM: dts: msm: enable the watchdog bark interrupt for smb138x

The smb138x parallel charger device has a watchdog timer that will
disable parallel charging if it is not pet by software. Enable it.

Change-Id: Ie28323cdabccdc64196fae25deb2f56dfbb5a0e7
Signed-off-by: Nicholas Troast <ntroast@codeaurora.org>