Add support for the 15'' MacBook Pro Retina. The keyboard is
the same as recent models.

The patch needs to be synchronized with the bcm5974 patch for
the trackpad - as usual.

Patch originally written by clipcarl (forums.opensuse.org).

[rydberg@euromail.se: Amended mouse ignore lines]
Signed-off-by: Ryan Bourgeois <bluedragonx@gmail.com>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>