pata_marvell: Add support for 88SE91A0, 88SE91A4

pata_marvell: Add support for 88SE91A0, 88SE91A4

BugLink: http://bugs.launchpad.net/bugs/777325

This patch enables support for Marvell IDE PATA controllers found on
Asus P8P67LE motherboard.

The formatting has been corrected and I also received a report from two
users of this motherboard that the patch works.

Signed-off-by: Paweł Drewniak <czajernia@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
(cherry picked from commit f920fe1cb74191a780d88937f36994231a8faba1)

Signed-off-by: Leann Ogasawara <leann.ogasawara@canonical.com>
Acked-by: Seth Forshee <seth.forshee@canonical.com>
Acked-by: Andy Whitcroft <apw@canonical.com>