HPCC-11874 Remove #define CHAR from the sources

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
Merge pull request #6227 from ghalliday/issue11874

HPCC-11874 Remove #define CHAR from the sources

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>