msm: synx: fix callback dispatch registered

The change fixes the callback handling if synx obj is destroyed
before it is signaled. Earlier the release would return fail if
the synx obj has not been signaled. But, this does not suit the
non-blocking wait where callback will be registered and the synx
obj will be ideally released and when the synx is signaled later
the registered callbacks will be invoked.
Change removes need for synx obj to be signaled before release
occurs. And in case if the synx obj deinit occurs without being
signaled, then registered callbacks will be dispatched with
cancelled status so any cleanup required by the client can be
achieved.

Change-Id: Ic4aed09bee2d818064db1bc415372eedd63d1872
Signed-off-by: Sumukh Hallymysore Ravindra <shallymy@codeaurora.org>