CONFIG_MACH_MX27 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

i.MX27 support

modulename: clock_imx27.ko

and/or

cpu_imx27.ko

configname: CONFIG_MACH_MX27

Linux Kernel Configuration
└─>i.MX27 support
In linux kernel since version 2.6.27 (release Date: 2008-10-09)  
This enables support for Freescale's MX2 based i.MX27 processor.

source code:
depends
CONFIG_ARCH_MX2

is selected by
CONFIG_MACH_MX27ADS

is depended by
CONFIG_SOC_IMX27