drm/syncobj: add timeline signal ioctl for syncobj v5

v2: individually allocate chain array, since chain node is free independently.
v3: all existing points must be already signaled before cpu perform signal operation,
    so add check condition for that.
v4: remove v3 change and add checking to prevent out-of-order
v5: unify binary and timeline

Signed-off-by: Chunming Zhou <david1.zhou@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Cc: Tobias Hector <Tobias.Hector@amd.com>
Cc: Jason Ekstrand <jason@jlekstrand.net>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Link: https://patchwork.freedesktop.org/patch/295792/?series=58813&rev=1