nm: Add --quiet to suppress "no symbols" diagnostic

	PR binutils/27408
	* readelf.c (quiet): New option flag.
	(enum long_option_values): New enum to hold long option value.
	(long_options): Add --quiet.
	(usage): Mention --quiet.
	(display_rel_file): If quiet is enabled, suppress "no symbols".
	(main): Handle the new option.
	* NEWS: Mention --quiet.
	* docs/binutils.texi: Document --quiet.