CONFIG_MACH_MSS2_DT is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Maxtor Shared Storage II (Flattened Device Tree)

modulename: board-mss2.ko

configname: CONFIG_MACH_MSS2_DT

Linux Kernel Configuration
└─>Marvell Orion
└─>Maxtor Shared Storage II (Flattened Device Tree)
In linux kernel since version 3.10 (release Date: 2013-06-30)  
Say 'Y' here if you want your kernel to support the
Maxtor Shared Storage II platform.

source code:
/arch/arm/mach-orion5x/board-mss2.c