btrfs: remove unused parameter from btrfs_prepare_extent_commit

Added but never used.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/ctree.h

@@ -2630,8 +2630,7 @@ int btrfs_free_reserved_extent(struct btrfs_fs_info *fs_info,
 			       u64 start, u64 len, int delalloc);
 int btrfs_free_and_pin_reserved_extent(struct btrfs_fs_info *fs_info,
 				       u64 start, u64 len);
-void btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
-				 struct btrfs_fs_info *fs_info);
+void btrfs_prepare_extent_commit(struct btrfs_fs_info *fs_info);
 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
 			       struct btrfs_fs_info *fs_info);
 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,

fs/btrfs/extent-tree.c

@@ -6558,8 +6558,7 @@ static int btrfs_free_reserved_bytes(struct btrfs_block_group_cache *cache,
 	spin_unlock(&space_info->lock);
 	return ret;
 }
-void btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
-				struct btrfs_fs_info *fs_info)
+void btrfs_prepare_extent_commit(struct btrfs_fs_info *fs_info)
 {
 	struct btrfs_caching_control *next;
 	struct btrfs_caching_control *caching_ctl;

fs/btrfs/transaction.c

@@ -2207,7 +2207,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans)
 		goto scrub_continue;
 	}
 
-	btrfs_prepare_extent_commit(trans, fs_info);
+	btrfs_prepare_extent_commit(fs_info);
 
 	cur_trans = fs_info->running_transaction;