* windres.c (usage): Add new --preprocessor-arg option.

	* windres.c (usage): Add new --preprocessor-arg option.
	(option_values): Add new OPTION_PREPROCESSOR_ARG enumerator.
	(option long_options): Add preprocessor-arg option.
	(main): Handle it.
	* doc/binutils.texi: Add documentation for --preprocessor-arg
	option.
	* NEWS: Add line about new --preprocessor-arg option for windres.

	* binutils-all/windres/windres.exp: Add '// cpparg <option>' command
	to rc file interpretation to specify addition pre-processor commands
	as script option.
	* binutils-all/windres/strtab3.rc: New.
	* binutils-all/windres/strtab3.rsd: New.
	* binutils-all/windres/README: Add note about cpparg script option.
	argument