CONFIG_MACH_NETSPACE_MAX_V2_DT is not available for thedefaultarchitecture x86.
Result is shown for architecture arm
default or selected kernelversion does not have config value CONFIG_MACH_NETSPACE_MAX_V2_DT.
Result is shown for kernelversion 6.2.5

LaCie Network Space Max v2 NAS (Flattened Device Tree)

modulename: board-ns2.ko

configname: CONFIG_MACH_NETSPACE_MAX_V2_DT

Linux Kernel Configuration
└─>Marvell Kirkwood Implementations
└─>LaCie Network Space Max v2 NAS (Flattened Device Tree)
In linux kernel since version 3.1 (release Date: 2011-10-24)  
Say 'Y' here if you want your kernel to support the LaCie
Network Space Max v2 NAS, using Flattened Device Tree.

source code: