msm: camera: add req_mgr tracepoints

Add camera event trace points for request manager:
cam_req_mgr_apply_request  - sending apply to nodes
cam_req_mgr_add_req	       - add request to tables
cam_req_mgr_connect_device - adding device in pipeline

These events allow us to track the state of devices
through the request manager to the various linked
devices.

Change-Id: Id92a9faae8f2a0595058d87d3bd22c37183532e1
Signed-off-by: Gregory Bergschneider <gbergsch@codeaurora.org>