hrtimer: Ensure timer is not running before migrating

A timer might be running when we are trying to move the timer to another
CPU so ensure that we wait for the timer to finish before migrating.

Change-Id: I4c9ee39c715baebfbdb8a50476a475e38b092f70
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
[rameezmustafa@codeaurora.org: Port to msm-4.9]
Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org>