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

Periodic Interval Timer (PIT) support


Linux Kernel Configuration
└─>AT91/Microchip SoCs
└─>Periodic Interval Timer (PIT) support
In linux kernel since version 5.1 (release Date: 2019-05-05)  
Select this to get a clocksource based on the Atmel Periodic Interval
Timer. It has a relatively low resolution and the TC Block clocksource
should be preferred.