rculist: move list_for_each_rcu() to where it belongs

rculist: move list_for_each_rcu() to where it belongs

The list_for_each_rcu() relies on the rcu_dereference() API which is not
provided by the list.h. At the same time list.h is a low-level basic header
that must not have dependencies like RCU, besides the fact of the potential
circular dependencies in some cases. With all that said, move RCU related
API to the rculist.h where it belongs.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Simona Vetter <simona.vetter@ffwll.ch>
Reviewed-by: "Paul E. McKenney" <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay (AMD) <neeraj.upadhyay@kernel.org>
Signed-off-by: "Paul E. McKenney" <paulmck@kernel.org>