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

LSI Axxia platforms

modulename: clk-axm5516.ko

configname: CONFIG_ARCH_AXXIA

Linux Kernel Configuration
└─>LSI Axxia platforms
In linux kernel since version 3.10 (release Date: 2013-06-30)  
This enables support for the LSI Axxia devices.

The LSI Axxia platforms require a Flattened Device Tree to be passed
to the kernel.

source code: