[PATCH] USB: usb-storage: add debug entry for REPORT LUNS

Bugs involving the REPORT LUNS SCSI-3 command are much easier to track
down if usb-storage displays the command's name, rather than "(Unknown
command)".

Signed-off-by: Paul Walmsley <paul@booyaka.com>
Cc: <mdharm-usb@one-eyed-alien.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>