The main problem was lack of proper QueryArena handling in
`period_setup_conds`. Since mysql_prepare_update/mysql_prepare_delete
are called during `PREPARE` statement, period conditions, should be
allocated on statement query arena.

Another problem is incorrect statement state handling in
period_setup_conds, which led to unexpected mysql_update termination.

* mysql_update: move period_setup_conds() to mysql_prepare_update to
  store conditions in statement's mem_root

* mtr: add period suite to default list, since --ps-protocol is now
  fixed

Fixes bugs:
MDEV-18853 Assertion `0' failed in Protocol::end_statement upon DELETE .. FOR PORTION via prepared statement
MDEV-18852 Server crashes in reinit_stmt_before_use upon UPDATE .. FOR PORTION via prepared statement