btrfs: remove leftover EXTENT_UPTODATE clear from an inode's io_tree

btrfs: remove leftover EXTENT_UPTODATE clear from an inode's io_tree

After commit 52b029f42751 ("btrfs: remove unnecessary EXTENT_UPTODATE
state in buffered I/O path") we never set EXTENT_UPTODATE in an inode's
io_tree anymore, but we still have some code attempting to clear that
bit from an inode's io_tree. Remove that code as it doesn't do anything
anymore. The sole use of the EXTENT_UPTODATE bit is for the excluded
extents io_tree (fs_info->excluded_extents), which is used to track the
locations of super blocks, so that their ranges are never marked as free,
making them unavailable for extent allocation.

Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>