Btrfs: use i_version instead of our own sequence

We've been keeping around the inode sequence number in hopes that somebody
would use it, but nobody uses it and people actually use i_version which
serves the same purpose, so use i_version where we used the incore inode's
sequence number and that way the sequence is updated properly across the
board, and not just in file write.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>

diff --cc fs/btrfs/btrfs_inode.h
Simple merge

diff --cc fs/btrfs/delayed-inode.c
Simple merge

diff --cc fs/btrfs/file.c
Simple merge

diff --cc fs/btrfs/inode.c
Simple merge

diff --cc fs/btrfs/ioctl.c
Simple merge

diff --cc fs/btrfs/super.c
Simple merge

diff --cc fs/btrfs/xattr.c
Simple merge