documentation: Update rcutree.kthread_prio for grace-period kthread use

Now that the rcutree.kthread_prio kernel boot parameter also controls
the priority of the grace-period kthreads, update the documentation to
reflect this change.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit is contained in:
Paul E. McKenney 2015-01-20 23:54:59 -08:00
commit d2af1ad73e