aoe: clean up printks via macros

Use simple macros to clean up the printks.
(This patch is reverted by the 14th patch to follow.)

Signed-off-by: "Ed L. Cashin" <ecashin@coraid.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>