omap: DMTIMER: Ack pending interrupt always when stopping a timer

omap: DMTIMER: Ack pending interrupt always when stopping a timer

The kernel timer queue is being run currently from a GP timer running in a one
shot mode, which works in a way that when it expires, it will also stop.
Usually during this situation, the interrupt handler will ack the interrupt,
load a new value to the timer and start it again. During suspend, the
situation is slightly different, as we disable interrupts just before
timekeeping is suspended, which leaves a small window where the timer can
expire before it is stopped, and will leave the interrupt flag pending.
This pending interrupt will prevent ARM sleep entry, thus now we ack it always
when we are attempting to stop a timer.

Signed-off-by: Tero Kristo <tero.kristo@nokia.com>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
[tony@atomide.com: removed the ifdef to make the patch cover omap1 also]
Signed-off-by: Tony Lindgren <tony@atomide.com>