libata: Avoid overflow in ata_tf_read_block() when tf->hba_lbal > 127

Phillip O'Donnell <phillip.odonnell@gmail.com> pointed out that the same
sign extension bug that was fixed in commit ba14a9c2 ("libata: Avoid
overflow in ata_tf_to_lba48() when tf->hba_lbal > 127") also appears to
exist in ata_tf_read_block().  Fix this by adding a cast to u64.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 0cd3ad4..4214bfb1 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -612,7 +612,7 @@
 		if (tf->flags & ATA_TFLAG_LBA48) {
 			block |= (u64)tf->hob_lbah << 40;
 			block |= (u64)tf->hob_lbam << 32;
-			block |= tf->hob_lbal << 24;
+			block |= (u64)tf->hob_lbal << 24;
 		} else
 			block |= (tf->device & 0xf) << 24;