btrfs: fix off-by-one end related to inode_need_compress()

btrfs: fix off-by-one end related to inode_need_compress()

In most cases btrfs uses @end as the inclusive end bytenr for a range,
and this applies to inode_need_compress().

However we have several sites not following the inclusive bytenr:

- run_delalloc_inline()
  Which assigned @blocksize as @end for inode_need_compress()

  This makes inode_need_compress() always skip the disk_i_size check.

- heuristic_collect_sample()
  Which assigned "start + BTRFS_MAX_UNCOMPRESSED" to @end, which is
  the exclusive bytenr.

Neither is really causing any real problem, as
heuristic_collect_sample() has proper checks to avoid reading anything
beyond @end, and the sampling read size is 16 bytes, so it has enough
headroom to handle that off-by-one problem.

But still I do not like anything out of the common scheme, so fix the
off-by-one @end for both call sites, and add extra ASSERT()s to catch
such unaligned parameters.

Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>