Add a --no-weak option to nm.

	PR 29135
	* nm.c (non_weak): New variable.
	(filter_symbols): When non-weak is true, ignore weak symbols.
	(long_options): Add --no-weak.
	(usage): Mention --no-weak.
	(main): Handle -W/--no-weak.
	* doc/binutils.texi: Document new feature.
	* NEWS: Mention the new feature.
	* testsuite/binutils-all/nm.exp: Add test of new feature.
	* testsuite/binutils-all/no-weak.s: New test source file.
6 files changed