CONFIG_MACH_BERLIN_BG2CD is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Marvell Armada 1500-mini (BG2CD)

modulename: bg2.ko

configname: CONFIG_MACH_BERLIN_BG2CD

Linux Kernel Configuration
└─>Marvell Berlin SoCs
└─>Marvell Armada 1500-mini (BG2CD)
In linux kernel since version 3.14 (release Date: 2014-03-30)  
source code:
drivers/clk/berlin/bg2.c