PR29362, some binutils memory leaks

2022-08-16  Alan Modra  <amodra@gmail.com>
	    Cunlong Li  <shenxiaogll@163.com>

	PR 29362
	* dwarf.c (free_debug_information): New function, extracted..
	(free_debug_memory): ..from here.
	(process_debug_info): Use it when before clearing out unit
	debug_information.  Clear all fields.
	* objcopy.c (delete_symbol_htabs): New function.
	(main): Call it via xatexit.
	(copy_archive): Free "dir".
	* objdump.c (free_debug_section): Free reloc_info.