The fix inserts newline and comma characters as appropriate
into the constraint reporting code to match the formatting
required by SHOW CREATE TABLE. Additionally, a erroneously
duplicated copy of check_if_incompatible_data() was removed
from db2i_constraints.cc since the correct version is already
in ha_ibmdb2i.cc.

storage/ibmdb2i/db2i_constraints.cc:
  Bug#49521 SHOW CREATE TABLE on IBMDB2I tables has incorrect fk constraint format
  
  - Insert newline and comma characters into the constraint reporting
    code to match the formatting required by SHOW CREATE TABLE.
  
  - Remove an erroneous copy of check_if_incompatible_data() from
    db2i_constraints.cc.