rcutorture: Adjust scenarios' Kconfig options for CONFIG_PREEMPT_DYNAMIC

Now that CONFIG_PREEMPT_DYNAMIC=y is the default, kernels that are
ostensibly built with CONFIG_PREEMPT_NONE=y or CONFIG_PREEMPT_VOLUNTARY=y
are now actually built with CONFIG_PREEMPT=y, but are by default booted
so as to disable preemption. Although this allows much more flexibility
from a single kernel binary, it means that the current rcutorture
scenarios won't find build errors that happen only when preemption is
fully disabled at build time.

This commit therefore adds CONFIG_PREEMPT_DYNAMIC=n to several scenarios,
and while in the area switches one from CONFIG_PREEMPT_NONE=y to
CONFIG_PREEMPT_VOLUNTARY=y to add coverage of this Kconfig option.

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

torture: Remove RCU_FAST_NO_HZ from rcu scenarios

All of the rcu scenarios that mentioning CONFIG_RCU_FAST_NO_HZ disable it.
But this Kconfig option is disabled by default, so this commit removes
the pointless "CONFIG_RCU_FAST_NO_HZ=n" lines from these scenarios.

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

rcutorture: Right-size TREE10 CPU consumption

The number of CPUs is tuned to allow "4*CFLIST TREE10" on a large system,
up from "3*CFLIST TREE10" previously.

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

rcutorture: Add 100-CPU configuration

The small-system rcutorture configurations have served us well for a great
many years, but it is now time to add a larger one. This commit does
just that, but does not add it to the defaults in CFLIST. This allows
the kvm.sh argument '--configs "4*CFLIST TREE10" to run four instances
of each of the default configurations concurrently with one instance of
the large configuration.

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