msm: kgsl: Fix context leak in aux_command ioctl

Currently, after timeline drawobj creation it is not
immediately added to local drawobj list as a result
if kgsl_drawobj_add_timeline fails this drawobj is
leaked. As the timeline drawobj upon creation takes
a refcount on the context this leak also results in
context leak. Fix this by adding timeline drawobj to
local drawobj list immediately after creation.

Change-Id: I30f85506595ad7a7c54e82a7e850c96e7cdcbefd
Signed-off-by: Harshdeep Dhatt <hdhatt@codeaurora.org>
Signed-off-by: Deepak Kumar <dkumar@codeaurora.org>