default or selected kernelversion does not have config value CONFIG_ARM_ARMADA_370_XP_CPUIDLE.
Result is shown for kernelversion 5.4.123
CPU Idle Driver for Armada 370/XP family processors
modulename: cpuidle-armada-370-xp.ko
configname: CONFIG_ARM_ARMADA_370_XP_CPUIDLE
Linux Kernel Configuration
└─>CPU Idle Driver for Armada 370/XP family processors
In linux kernel since version 3.16 (release Date: 2014-08-03)
Select this to enable cpuidle on Armada 370/XP processors.