timer: Improve the comment describing schedule_timeout()

 * schedule_timeout - sleep until timeout

 * @timeout: timeout value in jiffies

 *

 * Make the current task sleep until @timeout jiffies have

 * elapsed. The routine will return immediately unless

 * the current task state has been set (see set_current_state()).

 * Make the current task sleep until @timeout jiffies have elapsed.

 * The function behavior depends on the current task state

 * (see also set_current_state() description):

 *

 * You can set the task state as follows -

 * %TASK_RUNNING - the scheduler is called, but the task does not sleep

 * at all. That happens because sched_submit_work() does nothing for

 * tasks in %TASK_RUNNING state.

 *

 * %TASK_UNINTERRUPTIBLE - at least @timeout jiffies are guaranteed to

 * pass before the routine returns unless the current task is explicitly

 * woken up, (e.g. by wake_up_process())".

 * woken up, (e.g. by wake_up_process()).

 *

 * %TASK_INTERRUPTIBLE - the routine may return early if a signal is

 * delivered to the current task or the current task is explicitly woken

 * up.

 *

 * The current task state is guaranteed to be TASK_RUNNING when this

 * The current task state is guaranteed to be %TASK_RUNNING when this

 * routine returns.

 *

 * Specifying a @timeout value of %MAX_SCHEDULE_TIMEOUT will schedule