btrfs: add orig_logical to btrfs_bio for encryption

btrfs: add orig_logical to btrfs_bio for encryption

When checksumming the encrypted bio on writes we need to know which
logical address this checksum is for.  At the point where we get the
encrypted bio the bi_sector is the physical location on the target disk,
so we need to save the original logical offset in the btrfs_bio.  Then
we can use this when checksumming the bio instead of the
bio->iter.bi_sector.

Note: The patch was taken from v5 of fscrypt patchset
(https://lore.kernel.org/linux-btrfs/cover.1706116485.git.josef@toxicpanda.com/)
which was handled over time by various people: Omar Sandoval, Sweet Tea
Dorminy, Josef Bacik.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Daniel Vacek <neelx@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add note ]
Signed-off-by: David Sterba <dsterba@suse.com>