default or selected kernelversion does not have config value CONFIG_MLXSW_SWITCHIB.
Result is shown for kernelversion 6.9.9

Mellanox Technologies SwitchIB and SwitchIB-2 support

modulename: mlxsw_switchib.ko

configname: CONFIG_MLXSW_SWITCHIB

Linux Kernel Configuration
└─>Device Drivers
└─>Network device support
└─>Ethernet driver support
└─>Mellanox Technologies SwitchIB and SwitchIB-2 support
In linux kernel since version 4.1 (release Date: 2015-06-21)  
This driver supports Mellanox Technologies SwitchIB and SwitchIB-2
Infiniband Switch ASICs.

To compile this driver as a module, choose M here: the
module will be called mlxsw_switchib.

source code: