private void addHeaderField(StructureDataType struct, DataType dt, String fieldname,
			String comment) {
		if (headerSize > struct.getLength()) {
			struct.add(dt, fieldname, comment);
		}
	}
Gets architecture information.

@return architecture information
Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/macho/dyld/DyldCacheHeader.java