* dcrt0.cc (dll_crt0_0): Check for wincap.wow64_has_secondary_stack

	* dcrt0.cc (dll_crt0_0): Check for wincap.wow64_has_secondary_stack
	rather than for wincap.is_wow64.  Accommodate name change from
	wow64_has_64bit_parent to wow64_needs_stack_adjustment.  Align comment.
	(_dll_crt0): Ditto.
	* wincap.h (wincaps::wow64_has_secondary_stack): New element.
	* wincap.cc: Implement above element throughout.
	(wincapc::init): Set wow64_has_secondary_stack to false on non-64 bit
	systems.
	* wow64.cc (wow64_needs_stack_adjustment): Rename (hopefully the last
	time) from wow64_has_64bit_parent.
	(wow64_eval_expected_main_stack): Fix comment to reflect real life.
	(wow64_test_for_64bit_parent): Fix comment.
	* wow64.h (wow64_needs_stack_adjustment): Accommodate new name.