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

Xilinx Zynq ARM Cortex A9 Platform

modulename: clkc.ko

configname: CONFIG_ARCH_ZYNQ

Linux Kernel Configuration
└─>Xilinx Zynq ARM Cortex A9 Platform
In linux kernel since version 3.1 (release Date: 2011-10-24)  
Support for Xilinx Zynq ARM Cortex A9 Platform

source code:
drivers/clk/zynq/

is selected by
CONFIG_FB_XILINX