pata_hpt*, pata_serverworks: fix UDMA masking

When masking, mask out the modes that are unsupported not the ones
that are supported.  This makes life happier.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/pata_serverworks.c b/drivers/ata/pata_serverworks.c
index 9c523fb..a589c0f 100644
--- a/drivers/ata/pata_serverworks.c
+++ b/drivers/ata/pata_serverworks.c
@@ -226,7 +226,7 @@
 
 	for (i = 0; (p = csb_bad_ata100[i]) != NULL; i++) {
 		if (!strcmp(p, model_num))
-			mask &= ~(0x1F << ATA_SHIFT_UDMA);
+			mask &= ~(0xE0 << ATA_SHIFT_UDMA);
 	}
 	return ata_pci_default_filter(adev, mask);
 }