ubifs_idx_branch
br = ubifs_idx_branch(c, idx, child_cnt - 1);
br = ubifs_idx_branch(c, idx, iip);
br = ubifs_idx_branch(c, idx, iip + 1);
br = ubifs_idx_branch(c, idx, i);
br = ubifs_idx_branch(c, idx, 0);
struct ubifs_branch *br = ubifs_idx_branch(c, idx, i);
struct ubifs_branch *br = ubifs_idx_branch(c, idx, i);
struct ubifs_branch *br = ubifs_idx_branch(c, idx, i);