The opp binding now allows to have an empty opp table and shared-opp to still describe that devices share v/f lines. When initialising an empty opp table, allow such case by: - treating such conditions with warnings in place of errors - don't fail on empty table Signed-off-by: Nicola Mazzucato <nicola.mazzucato@arm.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>