[PATCH] ata_piix: allow 01b MAP for both ICH6M and ICH7M

ICH7M was separated from ICH6M to allow undocumented MAP value 01b
which was spotted on an ASUS notebook.  However, there is also
notebooks with MAP value 01b on ICH6M.  This patch re-merges ICH6M and
ICH7M entries and allows MAP value 01b for both.

This problem has been reported and initial patch provided by Jonathan
Dieter.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Jonathan Dieter <jdieter@gmail.com>
Cc: Tom Deblauwe <tom.deblauwe@telenet.be>
Signed-off-by: Jeff Garzik <jeff@garzik.org>