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

Xilinx Zynq ARM Cortex A9 Platform

configname: CONFIG_ARCH_ZYNQ

ARM system type
└─>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


depends
 or CONFIG_ARCH_MULTI_V7

is selected by
CONFIG_FB_XILINX