btr_cur_search_to_nth_level(), btr_search_guess_on_hash(),
btr_pcur_open_with_no_init_func(), row_sel_open_pcur():
Replace the parameter has_search_latch with the ahi_latch
(passed as NULL if the caller does not hold the latch).

btr_search_update_hash_node_on_insert(),
btr_search_update_hash_on_insert(),
btr_search_build_page_hash_index(): Add the parameter ahi_latch.

btr_search_x_lock(), btr_search_x_unlock(),
btr_search_s_lock(), btr_search_s_unlock(): Remove.