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

Generic Tegra board (FDT support)

modulename: board-paz00-pinmux.ko

and/or

board-harmony-pinmux.ko

and/or

board-seaboard-pinmux.ko

and/or

board-dt.ko

and/or

board-trimslice-pinmux.ko

and/or

board-dt-tegra20.ko

configname: CONFIG_MACH_TEGRA_DT

Linux Kernel Configuration
└─>Generic Tegra board (FDT support)
In linux kernel since version 3.1 (release Date: 2011-10-24)  
Support for generic nVidia Tegra boards using Flattened Device Tree

source code:
arch/arm/mach-tegra/board-dt.c
selects
CONFIG_USE_OF

depends
CONFIG_ARCH_TEGRA |
| CONFIG_ARCH_TEGRA_2x_SOC