cpuidle: dt: Return the correct numbers of parsed idle states

stable inclusion
from stable-v4.19.270
commit fff6b31b49d7d33151b401c9df4bbbecbe13cc72
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I6DPF8


CVE: NA

--------------------------------

[ Upstream commit ee3c2c8a ]

While we correctly skips to initialize an idle state from a disabled idle
state node in DT, the returned value from dt_init_idle_driver() don't get
adjusted accordingly. Instead the number of found idle state nodes are
returned, while the callers are expecting the number of successfully
initialized idle states from DT.

This leads to cpuidle drivers unnecessarily continues to initialize their
idle state specific data. Moreover, in the case when all idle states have
been disabled in DT, we would end up registering a cpuidle driver, rather
than relying on the default arch specific idle call.

Fixes: 9f14da34 ("drivers: cpuidle: implement DT based idle states infrastructure")
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com>