btrfs: move the snapshot drop related prototypes to extent-tree.h

These belong in extent-tree.h, they were missed because they were not
grouped with the other extent-tree.c prototypes.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/ctree.h

@@ -675,12 +675,6 @@ static inline int btrfs_next_item(struct btrfs_root *root, struct btrfs_path *p)
 	return btrfs_next_old_item(root, p, 0);
 }
 int btrfs_leaf_free_space(struct extent_buffer *leaf);
-int __must_check btrfs_drop_snapshot(struct btrfs_root *root, int update_ref,
-				     int for_reloc);
-int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
-			struct btrfs_root *root,
-			struct extent_buffer *node,
-			struct extent_buffer *parent);
 
 /* orphan.c */
 int btrfs_insert_orphan_item(struct btrfs_trans_handle *trans,

fs/btrfs/extent-tree.h

@@ -68,5 +68,11 @@ int btrfs_free_reserved_extent(struct btrfs_fs_info *fs_info,
 int btrfs_pin_reserved_extent(struct btrfs_trans_handle *trans, u64 start, u64 len);
 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans);
 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, struct btrfs_ref *generic_ref);
+int __must_check btrfs_drop_snapshot(struct btrfs_root *root, int update_ref,
+				     int for_reloc);
+int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
+			struct btrfs_root *root,
+			struct extent_buffer *node,
+			struct extent_buffer *parent);
 
 #endif