dio: Fix dio_bus_match() kerneldoc

The kerneldoc for dio_bus_match() was obviously copied from
dio_match_device(), but wasnt't updated for the different calling
context and semantics.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20200112165613.20960-3-geert@linux-m68k.org