Fix handle_getdents(): string not null terminated.

  >>> CID 1135676 (#1 of 1): String not null terminated (STRING_NULL)

  >>> 37. string_null_argument: Function "translate_path(...)" does
      not terminate string "*path".

  >>> 47. string_null: Passing unterminated string "path" to
      "translate_path(...)", which expects a null-terminated
      string. [note: because the previous iteration (37.) has failed]

  470                translate_path(tracee, path, fd, component, false);
Fix queue_item(): logically dead code.

  >>> CID 1135674 (#1 of 1): Logically dead code (DEADCODE)
      dead_error_line: Execution cannot reach this statement "return NULL;".

  >>> cond_notnull: Condition "item == NULL", taking false branch.
      Now the value of "item" is not NULL.

  77        if (item == NULL)
  78                return NULL;
  79
  80        item->load = talloc_strdup(item, value);

  >>> notnull: At condition "item == NULL", the value of "item" cannot be NULL.
      dead_error_condition: The condition "item == NULL" cannot be true.

  81        if (item == NULL)
Don't use the MAP_32BIT trick to emulate the heap on 64-bit architectures.

Fix the test-cases instead...  That way, all architectures use the same
algorithm.