CONFIG_MACH_MX53_ARD is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Support MX53 ARD platforms

modulename: board-mx53_ard.ko

configname: CONFIG_MACH_MX53_ARD

Linux Kernel Configuration
└─>Support MX53 ARD platforms
In linux kernel since version 3.1 (release Date: 2011-10-24)  
Include support for MX53 ARD platform. This includes specific
configurations for the board and its peripherals.

source code: