btrfs: tree-checker: Enhance btrfs_check_node output

commit bba4f29896c986c4cec17bc0f19f2ce644fceae1 upstream.

Use inline function to replace macro since we don't need
stringification.
(Macro still exists until all callers get updated)

And add more info about the error, and replace EIO with EUCLEAN.

For nr_items error, report if it's too large or too small, and output
the valid value range.

For node block pointer, added a new alignment checker.

For key order, also output the next key to make the problem more
obvious.

Signed-off-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
[ wording adjustments, unindented long strings ]
Signed-off-by: David Sterba <dsterba@suse.com>
[bwh: Backported to 4.9:
 - Use root->sectorsize instead of root->fs_info->sectorsize
 - BTRFS_NODEPTRS_PER_BLOCK() takes a root instead of an fs_info]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>