Don't create unnecessary output sections.

	Don't create unnecessary output sections.
	* ldlang.c (out_bfd_get_section_by_name): Remove.
	(wild_section): Call bfd_get_section_by_name rather than
	our_bfd_get_section_by_name.  Don't call wild_doit if there is no
	section.
	(lang_create_output_section_statements): Remove.
	(map_input_to_output_sections): For several cases, call init_os if
	it has not already been called.
	(lang_size_sections): If output section was not created, skip it.
	(lang_process): Don't call lan_create_output_section_statements.
	(lang_place_orphans): Skip files with just_syms_flags set to true.
	* ld.texinfo: Document change.