ACPI: processor: idle: Eliminate static variable flat_state_cnt

ACPI: processor: idle: Eliminate static variable flat_state_cnt

Instead of using static variable flat_state_cnt to pass data between
functions involved in the _LPI information processing, pass the current
number of "flattened" idle states to flatten_lpi_states() and make it
return the updated number of those states.  At the same time, use a
local variable called state_count to store the number of "flattened"
idle states found so far in acpi_processor_get_lpi_info().

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: lihuisong@huawei.com
Link: https://patch.msgid.link/10715991.nUPlyArG6x@rafael.j.wysocki