Problem: Clients running different values for auto_increment_increment
and doing concurrent inserts leads to "Duplicate key error" in one of them.

Analysis:
When auto_increment_increment value is reduced in a session,
InnoDB uses last auto_increment_increment value
to recalculate the autoinc value.
In case, some other session has inserted a value
with different auto_increment_increment, InnoDB recalculate
autoinc values based on current session previous auto_increment_increment
instead of considering the auto_increment_increment used for last insert
across all session

Fix:
revert 7acdf29c
a.k.a. 7c12a9e5
as it causing the bug.

Reviewed By:
Bin <bin.x.su@oracle.com>
Kevin <kevin.lewis@oracle.com>
RB#21777

Note: In MariaDB Server, earlier changes in
ae5bc059
for MDEV-533 require that the original test in
mysql/mysql-server@1ccd472d63a042d3237a55f5827239164219ef7e
be adjusted for MariaDB.

Also, ef47b625 (MDEV-8827)
had to be reverted after the upstream fix had been backported.