* libnlm.h (struct nlm_obj_tdata): Add nlm_cygnus_section_hdr

	* libnlm.h (struct nlm_obj_tdata): Add nlm_cygnus_section_hdr
	field.
	(nlm_cygnus_section_header): New accessor macro.
	* nlmcode.h (nlm_object_p): Free new tdata structure if failure.
	Add fixed sections before swapping in auxiliary headers.  After
	adding sections, treat errors as real, not as wrong format.
	(nlm_swap_auxiliary_headers_in): Swap in the sections header; add
	sections to the BFD for each section it describes.
	(nlm_swap_auxiliary_headers_out): Swap out the sections header.
	(nlm_compute_section_file_positions): Account for the size of the
	sections header.