binutils: Add new GNU format mode to `size` utility

binutils: Add new GNU format mode to `size` utility

The size tool currently defaults to berkeley format output.  However,
this output format has a weird quirk, read-only data is counted
against the text sections, not the data sections.

The code offers no real explanation for why this is, but I'm reluctant
to change it for two reasons, first, I'm assuming it probably makes
sense in some case that I'm not thinking of (maybe a target where
sections are not marked executable, and so there's no distinction
between read-only data and code), and second, the code has been this
way for at least 20 years, I worry that changing things now might
cause more confusion than it solves.

This commit then introduces a new output format for the size tool,
this new format displays the results in a similar manor to the
berkeley format, but counts read-only data in the data column, and
only executable sections are counted in the text column.

Given that this is a brand new output format I've gone ahead and
simplified things a little, while the berkeley format displays the
total twice, once in decimal and once in hex, the new display format
just displays the total in decimal.  Of course, there's still the
'--radix' option which can be used to display all the results in
hexadecimal or octal.

I've called the new format 'gnu', so '--format=gnu' or '-G' are used
to access it.

binutils/ChangeLog:

	* size.c (berkeley_format): Delete.
	(enum output_format): New enum.
	(selected_output_format): New variable.
	(usage): Update to mention GNU format.
	(main): Update to extract options, and select format as needed.
	Handle GNU format where needed.
	(berkeley_sum): Renamed to...
	(berkeley_or_gnu_sum): ...this, and updated to handle both formats.
	(berkeley_format): Renamed to...
	(berkeley_or_gnu_format): ...this, and updated to handle both
	formats.
	(print_sizes): Handle GNU format.
	* doc/binutils.texi (size): Document new GNU format.
	* testsuite/binutils-all/size.exp: Add test of extended
	functionality.
	* NEWS: Mention new functionality.