Change nm so that when it is running in POSIX compatible mode, it does not prefix...

Change nm so that when it is running in POSIX compatible mode, it does not prefix symbol values with 0.

	PR 24507
	* nm.c: (print_format): New variable.
	(value_format_32bit, value_format_64bit): Delete.
	(set_print_radix): Remove code to alter value_format strings.
	(set_output_format): Record chosen format in print_format.
	(get_print_format): New function - constructs a printf formatting
	string according to the requirements of size, radix, and output
	format.
	(print_value): Use get_print_format.
	* testsuite/binutils-all/nm.exp: Add tests of "nm --format=posix"
	and "nm -t d".