Fix oo classdef array

	A previous commit moved data_classes_end to the end of ALL class data
	subsections; a label is needed at the end of the first subsection as
	it contains the main class array.

kernel/kernel.s:
	add data_classdef_(start|end).

kernel/oo.s:
	use data_classdef_(start|end) instead of data_classes_(start|end).
Use pei-i386 for symbol table dumping.

util/symtab.pl:
	convert elf to pei-i386 instead of pe-i386 as the latter is not
	always supported.
	don't check the error code on copy since even a successful copy
	returns error.