[libata] fix ATAPI-enable typo

Dumb typo spotted by Mark Lord.
diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c
index 5582376..104fd9a 100644
--- a/drivers/scsi/libata-scsi.c
+++ b/drivers/scsi/libata-scsi.c
@@ -1470,7 +1470,7 @@
 	if (unlikely(!ata_dev_present(dev)))
 		return NULL;
 
-	if (atapi_enabled) {
+	if (!atapi_enabled) {
 		if (unlikely(dev->class == ATA_DEV_ATAPI))
 			return NULL;
 	}