CONFIG_PM is not available for thedefaultarchitecture x86.
Result is shown for architecture m68knommu
Power Management support
modulename: pm.ko
and/orsleep.ko
and/ormpc52xx_sleep.ko
and/orlite5200_sleep.ko
and/orsysfs.ko
configname: CONFIG_PM
uClinux/68k (w/o MMU) Kernel Configuration
└─>Power management options
└─>Power Management support
In linux kernel since version 2.6.12
Support processor power management modes