defconfig: apq8084: enable event timer feature

This feature allows drivers to register hard deadline events with the
low power manager driver. Specifically for display h/w vsync events,
cpu is woken up before vsync to improve vsync interrupt latency.

Change-Id: I1dd26f96965f777e033847448bb0426d959a7741
Signed-off-by: Huaibin Yang <huaibiny@codeaurora.org>