zorro: Use zorro_match_device() helper in zorro_bus_match()

Make zorro_bus_match() use the existing zorro_match_device() helper,
instead of open-coding the same operation.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20200112164949.20196-4-geert@linux-m68k.org