[PATCH] x86_64: don't copy command line twice

... reducing the amount of changes Xen has to do.

Signed-Off-By: Jan Beulich <jbeulich@novell.com>

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>