RCU library supporting quiescent state was introduced
in 19.05 release and has been around 4 releases, it
should be mature enough to remove the experimental tag.
Signed-off-by: Joyce Kong <joyce.kong@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Acked-by: David Christensen <drc@linux.vnet.ibm.com>