Add missing NEWS and manual bits for "set trace-buffer-size".

Add missing NEWS and manual bits for "set trace-buffer-size".

Add missing mention of the QTBuffer::size packet configuration
command, in both NEWS and manual.

gdb/
2013-04-02  Pedro Alves  <palves@redhat.com>

	* NEWS: Mention "set/show remote trace-buffer-size-packet".

gdb/doc/
2013-04-02  Pedro Alves  <palves@redhat.com>

	* gdb.texinfo (Remote Configuration) <set remote @var{name}-packet
	table>: Add entry for "trace-buffer-size".