xfs: remove pointless pointer increment in xfs_dir2_block_compact()

xfs_dir2_block_compact() is passed a pointer to *blp, and
advances it locally - but nobody uses the pointer (locally)
after that.

This behavior came about as part of prior refactoring,

20f7e9f3 xfs: factor dir2 block read operations

and looking at the code as it was before, it seems quite clear
that this change introduced a bug; the pre-refactoring code
expects blp to be modified after compaction.
And indeed it did; see this commit which fixed it:

37f13561 xfs: recalculate leaf entry pointer after compacting a dir2 block

So the bug was introduced & resolved in the 3.8 cycle.

Whoops.  Well, it's fixed now, and mystery solved; just remove
the now-pointless local increment of the blp pointer.

(I guess we should have run clang earlier!)
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

fs/xfs/xfs_dir2_block.c

@@ -319,7 +319,6 @@ xfs_dir2_block_compact(
 		(xfs_dir2_data_aoff_t)((char *)blp - (char *)hdr),
 		(xfs_dir2_data_aoff_t)((be32_to_cpu(btp->stale) - 1) * sizeof(*blp)),
 		needlog, &needscan);
-	blp += be32_to_cpu(btp->stale) - 1;
 	btp->stale = cpu_to_be32(1);
 	/*
 	 * If we now need to rebuild the bestfree map, do so.