CONFIG_ATMEL_SECURE_PM is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Atmel Secure PM support


Linux Kernel Configuration
└─>AT91/Microchip SoCs
└─>Atmel Secure PM support
In linux kernel since version 5.2 (release Date: 2019-07-07)  
When running under a TEE, the suspend mode must be requested to be set
at TEE level. When enable, this option will use secure monitor calls
to set the suspend level. PSCI is then used to enter suspend.