Running a SELECT query over an IBMDB2I table with a cp1250 character set
was producing an error 2027 (ibmdb2i error 2027: Error converting single-byte
sort sequence to UCS-2).

The QMY_DESCRIBE_RANGE API was returning error 2027 to the storage engine
because the CCSID used for a cp1250 column (870) does not match the CCSID
used by the DB2 sort sequences associated with cp1250_* collations (1153).
This was because the storage engine relies on a set of system APIs to
determine which CCSID value most closely matches a particular MySQL
character set. However, in the case of cp1250, the system is returning
CCSID 870, which does not have a codepoint for the euro symbol, making it
an incorrect match.

This patch overrides the selection of a compatible CCSID to always return
1153 for cp1250.

storage/ibmdb2i/db2i_charsetSupport.cc:
  Bug#45197 cp1250 character set with IBMDB2I generates 2027 error
  
  override the selection of a compatible CCSID to
  always return 1153 for cp1250.