staging/android: bring struct sync_pt back

Move the list_head members from sync_pt to struct fence was a mistake,
they will not be used by struct fence as planned before, so here we create
sync_pt again to bring the list heads back.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Sumit Semwal <sumit.semwal@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>