staging: olpc_dcon: remove unnecessary work pending test

Remove unnecessary work pending test before calling schedule_work().
It has been tested in queue_work_on() already. No functional changed.

Signed-off-by: Xie XiuQi <xiexiuqi@huawei.com>
Cc: Jens Frederich <jfrederich@gmail.com>
Cc: Daniel Drake <dsd@laptop.org>
Cc: Jon Nettleton <jon.nettleton@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>