arm/dt: msm8226: Add DT property for timer reset during PC

On 8226, the timers get reset during Power collapse. The idle core
should migrate the timers into a broadcast timer to be able to wakeup
from sleep. Low power code uses this flag to determine if timer keeps
its state.

Change-Id: I1d017772f9f94c61df72f246813fdacd1025ae77
Signed-off-by: Priyanka Mathur <pmathur@codeaurora.org>