ARM: dts: msm: remove dt entry for wdog absent register for 8994

Watchdog absent register is protected on 8994 v1 and so it cannot be
programmed from non secure context. Remove the DT entry for this register.

Change-Id: I40a8202b4902f2520070fab865976c90518ee35e
Signed-off-by: Sarangdhar Joshi <spjoshi@codeaurora.org>