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

HTC Herald

modulename: board-htcherald.ko

configname: CONFIG_MACH_HERALD

Linux Kernel Configuration
└─>TI OMAP1 specific features
└─>HTC Herald
In linux kernel since version 2.6.33 (release Date: 2010-02-24)  
HTC Herald smartphone support (AKA T-Mobile Wing, ...)

source code: