CONFIG_ARCH_AGILEX is not available for thedefaultarchitecture x86.
Result is shown for architecture arm64

Intel's Agilex SoCFPGA Family

modulename: clk-agilex.ko

and/or

clk-pll-s10.ko

configname: CONFIG_ARCH_AGILEX

Linux Kernel Configuration
└─>Platform selection
└─>Intel's Agilex SoCFPGA Family
In linux kernel since version 5.1 (release Date: 2019-05-05)  
This enables support for Intel's Agilex SoCFPGA Family.

source code:
drivers/clk/socfpga/clk-agilex.c