rcu: Update __call_rcu() comments

The __call_rcu() function's header comment refers to a cpu argument
that no longer exists, and the comment of the return path from
rcu_nocb_try_bypass() ignores the non-no-CBs CPU case.  This commit
therefore update both comments.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
1 file changed