Problem was that Field_bit used Field::hash() function that did not
know about using null-byte for storing bits.
Resulting in wrong length, which was caught by valgrind.

Solution: created a Field_bit::hash() that uses Field_bit::val_int()
and my_charset_bin-collation function hash_sort.
Also use the store function for platform independs


mysql-test/r/partition_datatype.result:
  Bug#33379: valgrind error in parts/partition_bit_myisam
  
  result file
  
  enabled bit datatype test
mysql-test/t/partition_datatype.test:
  Bug#33379: valgrind error in parts/partition_bit_myisam
  
  test file
  
  enabled bit datatype test
sql/field.cc:
  Bug#33379: valgrind error in parts/partition_bit_myisam
  
  Problem was that Field_bit used Field::hash() function that did not
  know about using null-byte for storing bits.
  Resulting in wrong length.
  
  Solution: created a Field_bit::hash() that uses Field_bit::val_int()
  and my_charset_bin-collation function hash_sort.
  Also use the store function for platform independens.
sql/field.h:
  Bug#33379: valgrind error in parts/partition_bit_myisam
  
  Problem was that Field_bit used Field::hash() function that did not
  know about using null-byte for storing bits.
  Resulting in wrong length.
  
  Solution: created a Field_bit::hash().