Moved tests requiring ucs2 from mix2_myisam.test to a separate unit.


mysql-test/include/mix2.inc:
  Moved tests requiring ucs2 to a separate unit
mysql-test/r/mix2_myisam.result:
  Moved tests requiring ucs2 to a separate unit
mysql-test/r/mix2_myisam_ucs2.result:
  Moved tests requiring ucs2 to a separate unit
mysql-test/include/mix2_ucs2.inc:
  Moved tests requiring ucs2 to a separate unit
mysql-test/t/mix2_myisam_ucs2.test:
  Moved tests requiring ucs2 to a separate unit