ide/macide: Convert Mac IDE driver to platform driver

Add platform devices for the Mac IDE controller variants. Convert the
macide module into a platform driver to support two of those variants.
For the third, use a generic "pata_platform" driver instead.
This enables automatic loading of the appropriate module and begins
the process of replacing the driver with libata alternatives.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Stan Johnson <userm57@yahoo.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Joshua Thompson <funaho@jurai.org>
References: commit 5ed0794c ("m68k/atari: Convert Falcon IDE drivers to platform drivers")
References: commit 7ad19a99 ("ide: officially deprecated the legacy IDE driver")
Link: https://lore.kernel.org/r/edd106dad1bbea32500601c6071f37a9f02a8004.1600901284.git.fthain@telegraphics.com.au


Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>