CONFIG_ARCH_SPARX5 is not available for the default architecture x86.
Result is shown for architecture arm64

ARMv8 based Microchip Sparx5 SoC family

modulename: clk-sparx5.ko
configname: CONFIG_ARCH_SPARX5

Linux Kernel Configuration
└─> Platform selection
└─> ARMv8 based Microchip Sparx5 SoC family

This enables support for the Microchip Sparx5 ARMv8-based
SoC family of TSN-capable gigabit switches.

The SparX-5 Ethernet switch family provides a rich set of
switching features such as advanced TCAM-based VLAN and QoS
processing enabling delivery of differentiated services, and
security through TCAM-based frame processing using versatile
content aware processor (VCAP).

source code: