nubus: Rename struct nubus_dev

It is misleading to call a functional resource a "device". In adopting
the Linux Driver Model, the struct device will be embedded in struct
nubus_board. That will compound the terminlogy problem because drivers
will bind with boards, not with functional resources. Avoid this by
renaming struct nubus_dev as struct nubus_rsrc. "Functional resource"
is the vendor's terminology so this helps avoid confusion.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>