Downgrade objdump fatal errors to non-fatal

Downgrade objdump fatal errors to non-fatal

	* objdump.c (slurp_symtab): Replace bfd_fatal calls with calls
	to my_bfd_nonfatal.
	(slurp_dynamic_symtab, disassemble_section): Likewise.
	(disassemble_data): Replace fatal call with non_fatal call, and
	set exit_status.  Don't error on non-existent dynamic relocs.
	Don't call bfd_fatal on bfd_canonicalize_dynamic_reloc error.
	(dump_ctf, dump_section_sframe): Replace bfd_fatal calls with
	calls to my_bfd_nonfatal and clean up memory.
	(dump_relocs_in_section): Don't call bfd_fatal on errors.
	(dump_dynamic_relocs): Likewise.
	(display_any_bfd): Make archive nesting too depp non_fatal.