[PATCH] libata: stop setting sdev->host->max_sectors for lba48 drives

Avoid changing sdev->host->max_sectors because it can prevent use of
non-lba48 drives on other ports of the same adapter.

Signed-off-by: Stuart Hayes <stuart_hayes@Dell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>