net/ethernet: Move mac89x0.c from apple to cirrus

Macintosh CS89x0 based ethernet cards use a Crystal Semiconductor (Now
Cirrus Logic) CS89x0 chip, so the mac89x0 driver should be in
drivers/net/ethernet/cirrus instead of drivers/net/ethernet/apple.

This also fixes a build problem, as the driver needs a header file from the
cirrus directory:

drivers/net/ethernet/apple/mac89x0.c:107:20: error: cs89x0.h: No such file or directory

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: David S. Miller <davem@davemloft.net>