When comparing or hashing a fixed length character string, using a NO_PAD
collation, any trailing PAD character was sent to the hash and compare functions,
such that they became significant, whet they were not supposed to.

Patch will now trim any such trailing spaces from a fixed length character string
if a NO_PAD collation is specified.

This patch will change the calculated hash value for any fixed
length character column, where:
 - The column is part of a primary key or an unique key.
 (and)
 - The column is a fixed length character column.
 (and)
 - The column use a NO_PAD collation (see below)

Thus, online upgrade will be broken for any deployments having tables
with the above properties. However, this will *not* affect any GA
versions of MySQL-Cluster, as NO_PAD collations were introduced as part of
UCA-9.0 collations in MySQL 8.0, and there are no 8.0 based
Cluster GA-releases yet.

Reviewed by : Mauritz Sundell <mauritz.sundell@oracle.com>