USB: Support for ELECOM LD-USB20 in pegasus

This patch is support LD-USB20 of the USB LAN device.
http://www2.elecom.co.jp/products/LD-USB20.html

 ( Japanese only )

I am using this device.
And, I confirmed work by using this patch.

Signed-off-by: Nobuhiro Iwamatsu <hemamu@t-base.ne.jp>
Acked-by: Petko Manolov <petkan@nucleusys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>