btrfs: cleanup recursive include of the same header

We have several headers that are including themselves, triggering clangd
warnings.
Such includes are caused by commit 602035d7fecf ("btrfs: add forward
declarations and headers, part 2").

Just remove such unnecessary include.

Reviewed-by: Filipe Manana <[e-mail]>
Signed-off-by: Qu Wenruo <[e-mail]>
Reviewed-by: David Sterba <[e-mail]>
Signed-off-by: David Sterba <[e-mail]>

fs/btrfs/btrfs_inode.h

···
 #include <uapi/linux/btrfs_tree.h>
 #include <trace/events/btrfs.h>
 #include "block-rsv.h"
-#include "btrfs_inode.h"
 #include "extent_map.h"
 #include "extent_io.h"
 #include "extent-io-tree.h"

fs/btrfs/extent_map.h

···
 #include <linux/list.h>
 #include <linux/refcount.h>
 #include "misc.h"
-#include "extent_map.h"
 #include "compression.h"
 
 struct btrfs_inode;

fs/btrfs/fs.h

···
 #include "extent-io-tree.h"
 #include "async-thread.h"
 #include "block-rsv.h"
-#include "fs.h"
 
 struct inode;
 struct super_block;

fs/btrfs/locking.h

···
 #include <linux/lockdep.h>
 #include <linux/percpu_counter.h>
 #include "extent_io.h"
-#include "locking.h"
 
 struct extent_buffer;
 struct btrfs_path;

fs/btrfs/lru_cache.h

···
 #include <linux/types.h>
 #include <linux/maple_tree.h>
 #include <linux/list.h>
-#include "lru_cache.h"
 
 /*
  * A cache entry. This is meant to be embedded in a structure of a user of