timer: Initialize global deferrable timer

Initialize timer_base_deferrable variables properly along with
the initialization of the per cpu timers.

Change-Id: I14599cb6ab2fcc657edc7489ee1a55535183e3db
Signed-off-by: Kyle Yan <kyan@codeaurora.org>
Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>