xfs: "optimize" buffer item log segment bitmap setting

Optimize the setting of full words of bits in xfs_buf_item_log_segment.
The optimization is purely within the bug triage process.  No functional
changes.

Coverity-id: 1446793
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/xfs/xfs_buf_item.c

@@ -851,7 +851,7 @@ xfs_buf_item_log_segment(
 	 * first_bit and last_bit.
 	 */
 	while ((bits_to_set - bits_set) >= NBWORD) {
-		*wordp |= 0xffffffff;
+		*wordp = 0xffffffff;
 		bits_set += NBWORD;
 		wordp++;
 	}