MDEV-14222 Unnecessary 'cascade' memory allocation for every updated row
when there is no FOREIGN KEY
This reverts the MySQL 5.7.2 change
377774689b
which introduced these problems. MariaDB 10.2.2 inherited these problems
in commit 2e814d4702.
The FOREIGN KEY CASCADE and SET NULL operations implemented as
procedural recursion are consuming more than 8 kilobytes of stack
(9 stack frames) per iteration in a non-debug GNU/Linux AMD64 build.
This is why we need to limit the maximum recursion depth to 15 steps
instead of the 255 that it used to be in MySQL 5.7 and MariaDB 10.2.
A corresponding change was made in MySQL 5.7.21 in
7b26dc98a6
This corruption was introduced in MDEV-13331. It would have been caught
by the MySQL 5.7 test innodb.update-cascade which MariaDB was missing
until now.
row_ins_check_foreign_constraint(): Never replace err == DB_LOCK_WAIT
with other values than DB_LOCK_WAIT_TIMEOUT.
