android: fix reference leak in sync_fence_create

According to the documentation sync_fence_create takes ownership of the point,
not a reference on the point.

This fixes a memory leak introduced in 3.17's android fence rework.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Colin Cross <ccross@google.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>