eliminate target_ops->deprecated_xfer_memory.

As no target uses it anymore, it can finally go away.

After removing the deprecated_xfer_memory handling from
default_xfer_partial, we can delete the latter, because the only thing
it does is delegate to the target beneath unconditionally, which is
what the delegator installed by target-delegates.c will do for us if
no to_xfer_partial method is installed.

This was the last user of de_fault, so that goes away too.

Tested on x86_64 Fedora 17.

gdb/
2014-01-16  Pedro Alves  <palves@redhat.com>

	* target.c (complete_target_initialization): Don't install
	default_xfer_partial as to_xfer_partial hook.
	(nomemory): Delete.
	(update_current_target): Don't INHERIT nor de_fault
	deprecated_xfer_memory.  Delete de_fault macro.
	(default_xfer_partial, deprecated_debug_xfer_memory): Delete.
	(setup_target_debug): Don't install a deprecated_xfer_memory hook.
	* target.h (struct target_ops) <deprecated_xfer_memory>: Delete
	field.
bsd-uthread.c: Don't install a to_xfer_partial method.

Whatever the comment about deprecated_xfer_memory referred to,
deprecated_xfer_memory is gone now.  There's no need to install a
target method that just delegates, as that's what the default
delegator does already.

Tested by building an --enable-targets=all gdb on x86_64 Fedora 17.

gdb/
2014-01-15  Pedro Alves  <palves@redhat.com>

	* bsd-uthread.c (bsd_uthread_xfer_partial): Delete function.
	(bsd_uthread_target): Don't install bsd_uthread_xfer_partial as
	to_xfer_partial method.